diff --git a/core/src/com/unciv/Constants.kt b/core/src/com/unciv/Constants.kt
index 031bb38422..d5524b8663 100644
--- a/core/src/com/unciv/Constants.kt
+++ b/core/src/com/unciv/Constants.kt
@@ -5,6 +5,7 @@ object Constants {
     const val settler = "Settler"
     const val greatGeneral = "Great General"
 
+    const val impassable = "Impassable"
     const val ocean = "Ocean"
     const val coast = "Coast"
     const val mountain = "Mountain"
diff --git a/core/src/com/unciv/logic/city/CityConstructions.kt b/core/src/com/unciv/logic/city/CityConstructions.kt
index a36e73df6f..2f1bd45188 100644
--- a/core/src/com/unciv/logic/city/CityConstructions.kt
+++ b/core/src/com/unciv/logic/city/CityConstructions.kt
@@ -210,7 +210,8 @@ class CityConstructions {
 
     //region state changing functions
     fun setTransients(){
-        builtBuildingObjects = ArrayList(builtBuildings.map { cityInfo.getRuleset().buildings[it]!! })
+        builtBuildingObjects = ArrayList(builtBuildings.map { cityInfo.getRuleset().buildings[it]
+                    ?: throw java.lang.Exception("Building $it is not found!")})
     }
 
     fun addProductionPoints(productionToAdd: Int) {
diff --git a/core/src/com/unciv/logic/civilization/CivilizationInfo.kt b/core/src/com/unciv/logic/civilization/CivilizationInfo.kt
index 76d94c11be..77bbe076cd 100644
--- a/core/src/com/unciv/logic/civilization/CivilizationInfo.kt
+++ b/core/src/com/unciv/logic/civilization/CivilizationInfo.kt
@@ -280,9 +280,9 @@ class CivilizationInfo {
     fun isAtWarWith(otherCiv:CivilizationInfo): Boolean {
         if (otherCiv.civName == civName) return false // never at war with itself
         if (otherCiv.isBarbarian() || isBarbarian()) return true
-        if (!diplomacy.containsKey(otherCiv.civName)) // not encountered yet
-            return false
-        return getDiplomacyManager(otherCiv).diplomaticStatus == DiplomaticStatus.War
+        val diplomacyManager = diplomacy[otherCiv.civName]
+                ?: return false // not encountered yet
+        return diplomacyManager.diplomaticStatus == DiplomaticStatus.War
     }
 
     fun isAtWar() = diplomacy.values.any { it.diplomaticStatus== DiplomaticStatus.War && !it.otherCiv().isDefeated() }
@@ -338,7 +338,8 @@ class CivilizationInfo {
      *  And if they civs on't yet know who they are then they don;t know if they're barbarians =\
      *  */
     fun setNationTransient(){
-        nation = gameInfo.ruleSet.nations[civName]!!
+        nation = gameInfo.ruleSet.nations[civName]
+                ?: throw java.lang.Exception("Nation $civName is not found!")
     }
 
     fun setTransients() {
@@ -451,13 +452,13 @@ class CivilizationInfo {
     }
 
     fun canEnterTiles(otherCiv: CivilizationInfo): Boolean {
-        if(otherCiv==this) return true
-        if(nation.isBarbarian() && gameInfo.turns >= gameInfo.difficultyObject.turnBarbariansCanEnterPlayerTiles) return true
-        if(!diplomacy.containsKey(otherCiv.civName)) // not encountered yet
-            return false
-        if(isAtWarWith(otherCiv)) return true
-        if(getDiplomacyManager(otherCiv).hasOpenBorders) return true
-        return false
+        if (otherCiv==this) return true
+        if (otherCiv.isBarbarian()) return true
+        if (nation.isBarbarian() && gameInfo.turns >= gameInfo.difficultyObject.turnBarbariansCanEnterPlayerTiles)
+            return true
+        val diplomacyManager = diplomacy[otherCiv.civName]
+                ?: return false // not encountered yet
+        return (diplomacyManager.hasOpenBorders || diplomacyManager.diplomaticStatus == DiplomaticStatus.War)
     }
 
     fun addNotification(text: String, location: Vector2?, color: Color) {
diff --git a/core/src/com/unciv/logic/map/MapUnit.kt b/core/src/com/unciv/logic/map/MapUnit.kt
index 7b98111c47..cbad7ee45f 100644
--- a/core/src/com/unciv/logic/map/MapUnit.kt
+++ b/core/src/com/unciv/logic/map/MapUnit.kt
@@ -39,6 +39,9 @@ class MapUnit {
     @Transient var doubleMovementInCoast = false
     @Transient var doubleMovementInForestAndJungle = false
     @Transient var doubleMovementInSnowTundraAndHills = false
+    @Transient var canEnterIceTiles = false
+    @Transient var cannotEnterOceanTiles = false
+    @Transient var cannotEnterOceanTilesUntilAstronomy = false
 
     lateinit var owner: String
     lateinit var name: String
@@ -134,11 +137,14 @@ class MapUnit {
         uniques.addAll(promotions.promotions.map { currentTile.tileMap.gameInfo.ruleSet.unitPromotions[it]!!.effect })
         tempUniques = uniques
 
-        if("Ignores terrain cost" in uniques) ignoresTerrainCost = true
-        if("Rough terrain penalty" in uniques) roughTerrainPenalty = true
-        if("Double movement in coast" in uniques) doubleMovementInCoast = true
-        if("Double movement rate through Forest and Jungle" in uniques) doubleMovementInForestAndJungle = true
-        if("Double movement in Snow, Tundra and Hills" in uniques) doubleMovementInSnowTundraAndHills = true
+        ignoresTerrainCost = ("Ignores terrain cost" in uniques)
+        roughTerrainPenalty = ("Rough terrain penalty" in uniques)
+        doubleMovementInCoast = ("Double movement in coast" in uniques)
+        doubleMovementInForestAndJungle = ("Double movement rate through Forest and Jungle" in uniques)
+        doubleMovementInSnowTundraAndHills = ("Double movement in Snow, Tundra and Hills" in uniques)
+        canEnterIceTiles = ("Can enter ice tiles" in uniques)
+        cannotEnterOceanTiles = ("Cannot enter ocean tiles" in uniques)
+        cannotEnterOceanTilesUntilAstronomy = ("Cannot enter ocean tiles until Astronomy" in uniques)
     }
 
     fun hasUnique(unique:String): Boolean {
@@ -307,7 +313,8 @@ class MapUnit {
     fun setTransients(ruleset: Ruleset) {
         promotions.unit=this
         mapUnitAction?.unit = this
-        baseUnit=ruleset.units[name]!!
+        baseUnit=ruleset.units[name]
+                ?: throw java.lang.Exception("Unit $name is not found!")
         updateUniques()
     }
 
diff --git a/core/src/com/unciv/logic/map/TileInfo.kt b/core/src/com/unciv/logic/map/TileInfo.kt
index 16c065bc83..d95ad3fd8a 100644
--- a/core/src/com/unciv/logic/map/TileInfo.kt
+++ b/core/src/com/unciv/logic/map/TileInfo.kt
@@ -363,7 +363,7 @@ open class TileInfo {
             if(!defencePercentString.startsWith("-")) defencePercentString = "+$defencePercentString"
             lineList += "[$defencePercentString] to unit defence".tr()
         }
-        if(getBaseTerrain().impassable) lineList += "Impassable".tr()
+        if(getBaseTerrain().impassable) lineList += Constants.impassable.tr()
 
         return lineList.joinToString("\n")
     }
diff --git a/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt b/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
index 27316627c1..4caae2447c 100644
--- a/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
+++ b/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
@@ -325,8 +325,7 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
                 && !(tile.isCityCenter() && tile.isCoastalTile()))
             return false
 
-        if (tile.terrainFeature == Constants.ice
-                && !unit.baseUnit.uniques.contains("Can enter ice tiles"))
+        if (tile.terrainFeature == Constants.ice && !unit.canEnterIceTiles)
             return false
 
         if (tile.isWater && unit.type.isLandUnit()) {
@@ -335,8 +334,8 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
                 return false
         }
         if (tile.isOcean && unit.civInfo.nation.unique != UniqueAbility.WAYFINDING) {
-            if (unit.baseUnit.uniques.contains("Cannot enter ocean tiles")) return false
-            if (unit.baseUnit.uniques.contains("Cannot enter ocean tiles until Astronomy")
+            if (unit.cannotEnterOceanTiles) return false
+            if (unit.cannotEnterOceanTilesUntilAstronomy
                     && !unit.civInfo.tech.isResearched("Astronomy"))
                 return false
         }
@@ -350,12 +349,9 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
             // AIs won't enter city-state's border.
         }
 
-        val unitsInTile = tile.getUnits()
-        if (unitsInTile.isNotEmpty()) {
-            val firstUnit = unitsInTile.first()
-            if (firstUnit.civInfo != unit.civInfo && unit.civInfo.isAtWarWith(firstUnit.civInfo))
-                return false
-        }
+        val firstUnit = tile.getUnits().firstOrNull()
+        if (firstUnit != null && firstUnit.civInfo != unit.civInfo && unit.civInfo.isAtWarWith(firstUnit.civInfo))
+            return false
 
         return true
     }
diff --git a/core/src/com/unciv/models/ruleset/tile/Terrain.kt b/core/src/com/unciv/models/ruleset/tile/Terrain.kt
index ad6f3b64bb..ebcad6828b 100644
--- a/core/src/com/unciv/models/ruleset/tile/Terrain.kt
+++ b/core/src/com/unciv/models/ruleset/tile/Terrain.kt
@@ -1,6 +1,7 @@
 package com.unciv.models.ruleset.tile
 
 import com.badlogic.gdx.graphics.Color
+import com.unciv.Constants
 import com.unciv.models.ruleset.Ruleset
 import com.unciv.models.stats.NamedStats
 import com.unciv.models.translations.tr
@@ -23,7 +24,10 @@ class Terrain : NamedStats() {
         if(uniques.isNotEmpty())
             sb.appendln(uniques.joinToString { it.tr() })
 
-        sb.appendln("{Movement cost}: $movementCost".tr())
+        if (impassable)
+            sb.appendln(Constants.impassable.tr())
+        else
+            sb.appendln("{Movement cost}: $movementCost".tr())
 
         if (defenceBonus != 0f)
             sb.appendln("{Defence bonus}: ".tr() + (defenceBonus * 100).toInt() + "%")
diff --git a/core/src/com/unciv/ui/CivilopediaScreen.kt b/core/src/com/unciv/ui/CivilopediaScreen.kt
index e7d66f1ea3..6af5931df6 100644
--- a/core/src/com/unciv/ui/CivilopediaScreen.kt
+++ b/core/src/com/unciv/ui/CivilopediaScreen.kt
@@ -3,9 +3,15 @@ package com.unciv.ui
 import com.unciv.ui.utils.AutoScrollPane as ScrollPane
 import com.badlogic.gdx.scenes.scene2d.Actor
 import com.badlogic.gdx.scenes.scene2d.ui.*
+import com.unciv.Constants
 import com.unciv.UncivGame
+import com.unciv.logic.map.TileInfo
 import com.unciv.models.ruleset.Ruleset
+import com.unciv.models.ruleset.tile.Terrain
+import com.unciv.models.ruleset.tile.TerrainType
 import com.unciv.models.translations.tr
+import com.unciv.ui.tilegroups.TileGroup
+import com.unciv.ui.tilegroups.TileSetStrings
 import com.unciv.ui.utils.*
 import java.util.*
 
@@ -15,16 +21,20 @@ class CivilopediaScreen(ruleset: Ruleset) : CameraStageBaseScreen() {
     private val categoryToEntries = LinkedHashMap<String, Collection<CivilopediaEntry>>()
     private val categoryToButtons = LinkedHashMap<String, Button>()
 
-    private val entrySelectTable = Table().apply { defaults().pad(5f) }
+    private val entrySelectTable = Table().apply { defaults().pad(6f) }
     val description = "".toLabel()
 
+
     fun select(category: String) {
         entrySelectTable.clear()
         for (entry in categoryToEntries[category]!!
                 .sortedBy { it.name.tr() }){  // Alphabetical order of localized names
             val entryButton = Button(skin)
             if(entry.image!=null)
-                entryButton.add(entry.image).size(50f).padRight(10f)
+                if (category=="Terrains")
+                    entryButton.add(entry.image).padRight(24f)
+                else
+                    entryButton.add(entry.image).size(50f).padRight(10f)
             entryButton.add(entry.name.toLabel())
             entryButton.onClick {
                 description.setText(entry.description)
@@ -35,29 +45,8 @@ class CivilopediaScreen(ruleset: Ruleset) : CameraStageBaseScreen() {
 
     init {
         onBackButtonClicked { UncivGame.Current.setWorldScreen() }
-        val buttonTable = Table()
-        buttonTable.pad(15f)
-        buttonTable.defaults().pad(10f)
-        val buttonTableScroll = ScrollPane(buttonTable)
 
-        val goToGameButton = TextButton("Close".tr(), skin)
-        goToGameButton.onClick {
-            game.setWorldScreen()
-            dispose()
-        }
-
-        val topTable = Table()
-        topTable.add(goToGameButton).pad(10f)
-        topTable.add(buttonTableScroll)
-
-        val entryTable = Table()
-        val splitPane = SplitPane(topTable, entryTable, true, skin)
-        splitPane.splitAmount = 0.2f
-        splitPane.setFillParent(true)
-
-        stage.addActor(splitPane)
-
-        description.setWrap(true)
+        val tileSetStrings = TileSetStrings()
 
         categoryToEntries["Buildings"] = ruleset.buildings.values
                 .map { CivilopediaEntry(it.name,it.getDescription(false, null,ruleset),
@@ -66,7 +55,8 @@ class CivilopediaScreen(ruleset: Ruleset) : CameraStageBaseScreen() {
                 .map { CivilopediaEntry(it.name,it.getDescription(ruleset),
                         ImageGetter.getResourceImage(it.name,50f)) }
         categoryToEntries["Terrains"] = ruleset.terrains.values
-                .map { CivilopediaEntry(it.name,it.getDescription(ruleset)) }
+                .map { CivilopediaEntry(it.name,it.getDescription(ruleset),
+                        terrainImage(it, ruleset, tileSetStrings) ) }
         categoryToEntries["Tile Improvements"] = ruleset.tileImprovements.values
                 .map { CivilopediaEntry(it.name,it.getDescription(ruleset,false),
                         ImageGetter.getImprovementIcon(it.name,50f)) }
@@ -87,6 +77,10 @@ class CivilopediaScreen(ruleset: Ruleset) : CameraStageBaseScreen() {
         categoryToEntries["Tutorials"] = tutorialController.getCivilopediaTutorials()
                 .map { CivilopediaEntry(it.key.replace("_"," "), it.value.joinToString("\n\n") { line -> line.tr() }) }
 
+        val buttonTable = Table()
+        buttonTable.pad(15f)
+        buttonTable.defaults().pad(10f)
+
         for (category in categoryToEntries.keys) {
             val button = TextButton(category.tr(), skin)
             button.style = TextButton.TextButtonStyle(button.style)
@@ -94,19 +88,74 @@ class CivilopediaScreen(ruleset: Ruleset) : CameraStageBaseScreen() {
             button.onClick { select(category) }
             buttonTable.add(button)
         }
-        select("Tutorials")
-        val sp = ScrollPane(entrySelectTable)
-        sp.setupOverscroll(5f, 1f, 200f)
-        entryTable.add(sp).width(Value.percentWidth(0.25f, entryTable)).height(Value.percentHeight(0.7f, entryTable))
+
+        buttonTable.pack()
+        buttonTable.width = stage.width
+        val buttonTableScroll = ScrollPane(buttonTable)
+
+        val goToGameButton = TextButton("Close".tr(), skin)
+        goToGameButton.onClick {
+            game.setWorldScreen()
+            dispose()
+        }
+
+        val topTable = Table()
+        topTable.add(goToGameButton).pad(10f)
+        topTable.add(buttonTableScroll)
+        topTable.pack()
+        //buttonTable.height = topTable.height
+
+        val entryTable = Table()
+        val splitPane = SplitPane(topTable, entryTable, true, skin)
+        splitPane.splitAmount = topTable.prefHeight / stage.height
+        entryTable.height = stage.height - topTable.prefHeight
+        splitPane.setFillParent(true)
+
+        stage.addActor(splitPane)
+
+        description.setWrap(true)
+
+        val entrySelectScroll = ScrollPane(entrySelectTable)
+        entrySelectScroll.setupOverscroll(5f, 1f, 200f)
+        entryTable.add(entrySelectScroll)
+                .width(Value.percentWidth(0.25f, entryTable))
+                .fillY()
                 .pad(Value.percentWidth(0.02f, entryTable))
         entryTable.add(ScrollPane(description)).colspan(4)
                 .width(Value.percentWidth(0.65f, entryTable))
-                .height(Value.percentHeight(0.7f, entryTable))
+                .fillY()
                 .pad(Value.percentWidth(0.02f, entryTable))
         // Simply changing these to x*width, y*height won't work
 
-        buttonTable.width = stage.width
+        select("Tutorials")
     }
 
+    private fun terrainImage (terrain: Terrain, ruleset: Ruleset, tileSetStrings: TileSetStrings ): Actor? {
+        val tileInfo = TileInfo()
+        tileInfo.ruleset = ruleset
+        when(terrain.type) {
+            TerrainType.NaturalWonder -> {
+                tileInfo.naturalWonder = terrain.name
+                tileInfo.baseTerrain = terrain.turnsInto ?: Constants.grassland
+            }
+            TerrainType.TerrainFeature -> {
+                tileInfo.terrainFeature = terrain.name
+                tileInfo.baseTerrain = terrain.occursOn?.last() ?: Constants.grassland
+            }
+            else ->
+                tileInfo.baseTerrain = terrain.name
+        }
+        tileInfo.setTransients()
+        val group = TileGroup(tileInfo, TileSetStrings())
+        group.showEntireMap = true
+        group.forMapEditorIcon = true
+        group.update()
+        return group
+//        val wrapper = Table()
+//        wrapper.add(group).pad(24f)
+//        wrapper.pad(2f,24f,2f,24f)
+//        wrapper.debug = true
+//        return wrapper
+    }
 }
 
diff --git a/core/src/com/unciv/ui/mapeditor/MapEditorMenuPopup.kt b/core/src/com/unciv/ui/mapeditor/MapEditorMenuPopup.kt
index aa47f5b5db..eeef480f83 100644
--- a/core/src/com/unciv/ui/mapeditor/MapEditorMenuPopup.kt
+++ b/core/src/com/unciv/ui/mapeditor/MapEditorMenuPopup.kt
@@ -12,6 +12,8 @@ import com.unciv.logic.map.RoadStatus
 import com.unciv.models.translations.tr
 import com.unciv.ui.saves.Gzip
 import com.unciv.ui.utils.Popup
+import com.unciv.ui.utils.enable
+import com.unciv.ui.utils.isEnabled
 import com.unciv.ui.utils.onClick
 import com.unciv.ui.worldscreen.mainmenu.DropBox
 import kotlin.concurrent.thread
@@ -19,8 +21,10 @@ import kotlin.concurrent.thread
 class MapEditorMenuPopup(mapEditorScreen: MapEditorScreen): Popup(mapEditorScreen){
     init{
         val mapNameEditor = TextField(mapEditorScreen.mapName, skin)
-        mapNameEditor.addListener{ mapEditorScreen.mapName=mapNameEditor.text; true }
-        add(mapNameEditor).row()
+        add(mapNameEditor).fillX().row()
+        mapNameEditor.selectAll()
+        mapNameEditor.maxLength = 240       // A few under max for most filesystems
+        mapEditorScreen.stage.keyboardFocus = mapNameEditor
 
         val newMapButton = TextButton("New map".tr(),skin)
         newMapButton.onClick {
@@ -51,10 +55,28 @@ class MapEditorMenuPopup(mapEditorScreen: MapEditorScreen): Popup(mapEditorScree
         saveMapButton.onClick {
             mapEditorScreen.tileMap.mapParameters.name=mapEditorScreen.mapName
             mapEditorScreen.tileMap.mapParameters.type=MapType.custom
-            MapSaver.saveMap(mapEditorScreen.mapName,mapEditorScreen.tileMap)
-            UncivGame.Current.setWorldScreen()
+            thread ( name = "SaveMap" ) {
+                try {
+                    MapSaver.saveMap(mapEditorScreen.mapName, mapEditorScreen.tileMap)
+                    UncivGame.Current.setWorldScreen()
+                } catch (ex: Exception) {
+                    ex.printStackTrace()
+                    Gdx.app.postRunnable {
+                        val cantLoadGamePopup = Popup(mapEditorScreen)
+                        cantLoadGamePopup.addGoodSizedLabel("It looks like your map can't be saved!").row()
+                        cantLoadGamePopup.addCloseButton()
+                        cantLoadGamePopup.open(force = true)
+                    }
+                }
+            }
         }
+        saveMapButton.isEnabled = mapNameEditor.text.isNotEmpty()
         add(saveMapButton).row()
+        mapNameEditor.addListener {
+            mapEditorScreen.mapName = mapNameEditor.text
+            saveMapButton.isEnabled = mapNameEditor.text.isNotEmpty()
+            true
+        }
 
         val copyMapAsTextButton = TextButton("Copy to clipboard".tr(), skin)
         copyMapAsTextButton.onClick {
diff --git a/core/src/com/unciv/ui/mapeditor/MapEditorScreen.kt b/core/src/com/unciv/ui/mapeditor/MapEditorScreen.kt
index 14f1522f02..eede9a7460 100644
--- a/core/src/com/unciv/ui/mapeditor/MapEditorScreen.kt
+++ b/core/src/com/unciv/ui/mapeditor/MapEditorScreen.kt
@@ -18,7 +18,7 @@ import com.unciv.ui.utils.setFontSize
 
 class MapEditorScreen(): CameraStageBaseScreen() {
     val ruleset = RulesetCache.getBaseRuleset()
-    var mapName = "My first map"
+    var mapName = ""
 
     var tileMap = TileMap()
     lateinit var mapHolder: EditorMapHolder
diff --git a/core/src/com/unciv/ui/saves/LoadGameScreen.kt b/core/src/com/unciv/ui/saves/LoadGameScreen.kt
index 66a871c25a..34dcc256b9 100644
--- a/core/src/com/unciv/ui/saves/LoadGameScreen.kt
+++ b/core/src/com/unciv/ui/saves/LoadGameScreen.kt
@@ -42,11 +42,13 @@ class LoadGameScreen : PickerScreen() {
                 if (ex is UncivShowableException && ex.localizedMessage != null) {
                     // thrown exceptions are our own tests and can be shown to the user
                     cantLoadGamePopup.addGoodSizedLabel(ex.localizedMessage).row()
+                    cantLoadGamePopup.addCloseButton()
                     cantLoadGamePopup.open()
                 } else {
                     cantLoadGamePopup.addGoodSizedLabel("If you could copy your game data (\"Copy saved game to clipboard\" - ").row()
                     cantLoadGamePopup.addGoodSizedLabel("  paste into an email to yairm210@hotmail.com)").row()
                     cantLoadGamePopup.addGoodSizedLabel("I could maybe help you figure out what went wrong, since this isn't supposed to happen!").row()
+                    cantLoadGamePopup.addCloseButton()
                     cantLoadGamePopup.open()
                     ex.printStackTrace()
                 }
diff --git a/core/src/com/unciv/ui/utils/CameraStageBaseScreen.kt b/core/src/com/unciv/ui/utils/CameraStageBaseScreen.kt
index 803e4ae452..eb47635180 100644
--- a/core/src/com/unciv/ui/utils/CameraStageBaseScreen.kt
+++ b/core/src/com/unciv/ui/utils/CameraStageBaseScreen.kt
@@ -113,7 +113,10 @@ fun Button.enable() {
     color = Color.WHITE
     touchable = Touchable.enabled
 }
-
+var Button.isEnabled: Boolean
+    //Todo: Use in PromotionPickerScreen, TradeTable, WorldScreen.updateNextTurnButton
+    get() = touchable == Touchable.enabled
+    set(value) = if (value) enable() else disable()
 
 fun colorFromRGB(r: Int, g: Int, b: Int): Color {
     return Color(r/255f, g/255f, b/255f, 1f)
diff --git a/core/src/com/unciv/ui/worldscreen/WorldMapHolder.kt b/core/src/com/unciv/ui/worldscreen/WorldMapHolder.kt
index de1661ae7e..989ca8f44e 100644
--- a/core/src/com/unciv/ui/worldscreen/WorldMapHolder.kt
+++ b/core/src/com/unciv/ui/worldscreen/WorldMapHolder.kt
@@ -14,6 +14,7 @@ import com.unciv.logic.automation.UnitAutomation
 import com.unciv.logic.city.CityInfo
 import com.unciv.logic.civilization.CivilizationInfo
 import com.unciv.logic.map.*
+import com.unciv.models.AttackableTile
 import com.unciv.models.UncivSound
 import com.unciv.models.ruleset.unit.UnitType
 import com.unciv.ui.map.TileGroupMap
@@ -261,23 +262,24 @@ class WorldMapHolder(internal val worldScreen: WorldScreen, internal val tileMap
                         if (UncivGame.Current.settings.singleTapMove || isAirUnit) 0.7f else 0.3f)
         }
 
-        val unitType = unit.type
-        val attackableTiles: List<TileInfo> = if (unitType.isCivilian()) listOf()
+        val attackableTiles: List<AttackableTile> = if (unit.type.isCivilian()) listOf()
         else {
-            val tiles = BattleHelper.getAttackableEnemies(unit, unit.movement.getDistanceToTiles()).map { it.tileToAttack }
-            tiles.filter { (UncivGame.Current.viewEntireMapForDebug || playerViewableTilePositions.contains(it.position)) }
+            BattleHelper.getAttackableEnemies(unit, unit.movement.getDistanceToTiles())
+                    .filter { (UncivGame.Current.viewEntireMapForDebug ||
+                            playerViewableTilePositions.contains(it.tileToAttack.position)) }
+                    .distinctBy { it.tileToAttack }
         }
 
         for (attackableTile in attackableTiles) {
 
-            tileGroups[attackableTile]!!.showCircle(colorFromRGB(237, 41, 57))
-
-            val distance = unit.currentTile.aerialDistanceTo(attackableTile)
-            if (distance > unit.getRange())
-                tileGroups[attackableTile]!!.showCrosshair(colorFromRGB(255, 75, 0))
-            else
-                tileGroups[attackableTile]!!.showCrosshair(Color.RED)
+            tileGroups[attackableTile.tileToAttack]!!.showCircle(colorFromRGB(237, 41, 57))
 
+            tileGroups[attackableTile.tileToAttack]!!.showCrosshair (
+                    // the targets which cannot be attacked without movements shown as orange-ish
+                    if (attackableTile.tileToAttackFrom != unit.currentTile)
+                         colorFromRGB(255, 75, 0)
+                    else Color.RED
+            )
         }
 
         // Fade out less relevant images if a military unit is selected
diff --git a/tests/src/com/unciv/logic/map/UnitMovementAlgorithmsTests.kt b/tests/src/com/unciv/logic/map/UnitMovementAlgorithmsTests.kt
new file mode 100644
index 0000000000..ecc29f5bf1
--- /dev/null
+++ b/tests/src/com/unciv/logic/map/UnitMovementAlgorithmsTests.kt
@@ -0,0 +1,238 @@
+//  Taken from https://github.com/TomGrill/gdx-testing
+package com.unciv.logic.map
+
+import com.unciv.Constants
+import com.unciv.logic.city.CityInfo
+import com.unciv.logic.civilization.CivilizationInfo
+import com.unciv.logic.civilization.diplomacy.DiplomacyManager
+import com.unciv.logic.civilization.diplomacy.DiplomaticStatus
+import com.unciv.models.ruleset.Nation
+import com.unciv.models.ruleset.Ruleset
+import com.unciv.models.ruleset.RulesetCache
+import com.unciv.models.ruleset.unit.BaseUnit
+import com.unciv.models.ruleset.unit.UnitType
+import com.unciv.testing.GdxTestRunner
+import org.junit.Assert
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(GdxTestRunner::class)
+class UnitMovementAlgorithmsTests {
+
+    private var tile = TileInfo()
+    private var civInfo = CivilizationInfo()
+    private var ruleSet = Ruleset()
+    private var unit = MapUnit()
+
+    @Before
+    fun initTheWorld() {
+        RulesetCache.loadRulesets()
+        ruleSet = RulesetCache.getBaseRuleset()
+        tile.ruleset = ruleSet
+        civInfo.tech.techsResearched.addAll(ruleSet.technologies.keys)
+        civInfo.tech.embarkedUnitsCanEnterOcean = true
+        civInfo.tech.unitsCanEmbark = true
+        civInfo.nation = Nation().apply {
+            name = "My nation"
+            cities = arrayListOf("The Capital")
+        }
+        unit.civInfo = civInfo
+    }
+
+    @Test
+    fun canPassThroughPassableTerrains() {
+        for (terrain in ruleSet.terrains.values) {
+            tile.baseTerrain = terrain.name
+            tile.setTransients()
+
+            unit.baseUnit = BaseUnit().apply { unitType = UnitType.Melee }
+
+            Assert.assertTrue(terrain.name, terrain.impassable != unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun unitCanEnterTheCity() {
+        val map = TileMap()
+        tile.baseTerrain = Constants.hill
+        tile.tileMap = map
+        tile.setTransients()
+
+        val otherTile = tile.clone()
+        otherTile.baseTerrain = Constants.coast
+        otherTile.position.y = 1f
+
+        map.tileMatrix.add(arrayListOf(tile, otherTile))
+
+        val city = CityInfo()
+        city.location = tile.position
+        city.civInfo = civInfo
+        tile.owningCity = city
+
+        for (type in UnitType.values())
+        {
+            unit.owner = civInfo.civName
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+            Assert.assertTrue(type.name, unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun waterUnitCanNOTEnterLand() {
+        for (terrain in ruleSet.terrains.values) {
+            if (terrain.impassable) continue
+            tile.baseTerrain = terrain.name
+            tile.setTransients()
+
+            for (type in UnitType.values()) {
+                if (type == UnitType.City) continue
+                unit.baseUnit = BaseUnit().apply { unitType = type }
+                Assert.assertTrue("%s cannot be at %s".format(type, terrain.name),
+                        (type.isWaterUnit() && tile.isLand) != unit.movement.canPassThrough(tile))
+            }
+        }
+    }
+
+    @Test
+    fun canNOTEnterIce() {
+        tile.baseTerrain = Constants.ocean
+        tile.terrainFeature = Constants.ice
+        tile.setTransients()
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+
+            if (type == UnitType.WaterSubmarine) {
+                unit.baseUnit.uniques.add("Can enter ice tiles")
+            }
+            unit.updateUniques()
+
+            Assert.assertTrue("$type cannot be in Ice",
+                    (type == UnitType.WaterSubmarine) == unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun canNOTEnterNaturalWonder() {
+        tile.baseTerrain = Constants.plains
+        tile.naturalWonder = "Wonder Thunder"
+        tile.setTransients()
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+
+            Assert.assertFalse("$type must not enter Wonder tile", unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun canNOTEnterCoastUntilProperTechIsResearched() {
+
+        civInfo.tech.unitsCanEmbark = false
+
+        tile.baseTerrain = Constants.coast
+        tile.setTransients()
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+
+            Assert.assertTrue("$type cannot be in Coast",
+                    unit.type.isLandUnit() != unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun canNOTEnterOceanUntilProperTechIsResearched() {
+
+        civInfo.tech.embarkedUnitsCanEnterOcean = false
+
+        tile.baseTerrain = Constants.ocean
+        tile.setTransients()
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+
+            Assert.assertTrue("$type cannot be in Ocean",
+                    unit.type.isLandUnit() != unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun canNOTEnterOceanWithLimitations() {
+
+        tile.baseTerrain = Constants.ocean
+        tile.setTransients()
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply {
+                unitType = type
+                if (type == UnitType.Melee)
+                    uniques.add("Cannot enter ocean tiles")
+                if (type == UnitType.Ranged)
+                    uniques.add("Cannot enter ocean tiles until Astronomy")
+            }
+            unit.updateUniques()
+
+            Assert.assertTrue("$type cannot be in Ocean",
+                    (type == UnitType.Melee) != unit.movement.canPassThrough(tile))
+
+            civInfo.tech.techsResearched.remove("Astronomy")
+
+            Assert.assertTrue("$type cannot be in Ocean until Astronomy",
+                    (type == UnitType.Melee ||
+                              type == UnitType.Ranged) != unit.movement.canPassThrough(tile))
+
+            civInfo.tech.techsResearched.add("Astronomy")
+        }
+    }
+
+    @Test
+    fun canNOTPassThroughTileWithEnemyUnits() {
+        tile.baseTerrain = Constants.grassland
+        tile.setTransients()
+
+        val otherCiv = CivilizationInfo()
+        otherCiv.civName = "Barbarians" // they are always enemies
+        otherCiv.nation = Nation().apply { name = "Barbarians" }
+        val otherUnit = MapUnit()
+        otherUnit.civInfo = otherCiv
+        tile.militaryUnit = otherUnit
+
+        for (type in UnitType.values()) {
+            unit.baseUnit = BaseUnit().apply { unitType = type }
+
+            Assert.assertFalse("$type must not enter occupied tile", unit.movement.canPassThrough(tile))
+        }
+    }
+
+    @Test
+    fun canNOTPassForeignTiles() {
+        tile.baseTerrain = Constants.desert
+        tile.setTransients()
+
+        val otherCiv = CivilizationInfo()
+        otherCiv.civName = "Other civ"
+        otherCiv.nation = Nation().apply { name = "Other nation" }
+
+        val city = CityInfo()
+        city.location = tile.position.cpy().add(1f,1f)
+        city.civInfo = otherCiv
+        tile.owningCity = city
+
+        unit.baseUnit = BaseUnit().apply { unitType = UnitType.Melee }
+        unit.owner = civInfo.civName
+
+        Assert.assertFalse("Unit must not enter other civ tile", unit.movement.canPassThrough(tile))
+
+        city.location = tile.position
+
+        Assert.assertFalse("Unit must not enter other civ city", unit.movement.canPassThrough(tile))
+
+        city.hasJustBeenConquered = true
+        civInfo.diplomacy["Other civ"] = DiplomacyManager(otherCiv, "Other civ")
+        civInfo.getDiplomacyManager(otherCiv).diplomaticStatus = DiplomaticStatus.War
+
+        Assert.assertTrue("Unit can capture other civ city", unit.movement.canPassThrough(tile))
+    }
+}
\ No newline at end of file