diff --git a/core/src/com/unciv/logic/automation/WorkerAutomation.kt b/core/src/com/unciv/logic/automation/WorkerAutomation.kt
index 1c35d5609f..b5bd141ae6 100644
--- a/core/src/com/unciv/logic/automation/WorkerAutomation.kt
+++ b/core/src/com/unciv/logic/automation/WorkerAutomation.kt
@@ -102,7 +102,7 @@ class WorkerAutomation(val unit: MapUnit) {
                             && (it.improvement == null || (it.hasViewableResource(unit.civInfo) && !it.containsGreatImprovement() && it.getTileResource().improvement != it.improvement))
                             && it.isLand()
                             && !it.getBaseTerrain().impassable
-                            && it.canBuildImprovement(chooseImprovement(it, unit.civInfo), unit.civInfo)
+                            && (it.containsUnfinishedGreatImprovement() || it.canBuildImprovement(chooseImprovement(it, unit.civInfo), unit.civInfo))
                             && {val city=it.getCity();  city==null || it.getCity()?.civInfo == unit.civInfo}() // don't work tiles belonging to another civ
                 }.sortedByDescending { getPriority(it, unit.civInfo) }.toMutableList()
 
@@ -145,6 +145,7 @@ class WorkerAutomation(val unit: MapUnit) {
             tile.improvementInProgress != null -> tile.improvementInProgress
             improvementStringForResource != null -> improvementStringForResource
             tile.containsGreatImprovement() -> null
+            tile.containsUnfinishedGreatImprovement() -> null
             tile.terrainFeature == "Jungle" -> "Trading post"
             tile.terrainFeature == "Marsh" -> "Remove Marsh"
             tile.terrainFeature == "Forest" -> "Lumber mill"
diff --git a/core/src/com/unciv/logic/map/TileInfo.kt b/core/src/com/unciv/logic/map/TileInfo.kt
index 99de44f996..7c4b92aa92 100644
--- a/core/src/com/unciv/logic/map/TileInfo.kt
+++ b/core/src/com/unciv/logic/map/TileInfo.kt
@@ -45,8 +45,13 @@ open class TileInfo {
     }
 
     fun containsGreatImprovement(): Boolean {
-        if (getTileImprovement() == null) return false
-        return getTileImprovement()!!.name in listOf("Academy", "Landmark", "Manufactory", "Customs house")
+        if (improvement in listOf("Academy", "Landmark", "Manufactory", "Customs house")) return true
+        return false
+    }
+
+    fun containsUnfinishedGreatImprovement(): Boolean {
+        if (improvementInProgress in listOf("Academy", "Landmark", "Manufactory", "Customs house")) return true
+        return false
     }
 
     //region pure functions