diff --git a/OpenRA.Game/Map/CellLayer.cs b/OpenRA.Game/Map/CellLayer.cs
index 1680d8f33f..b1e975a3b3 100644
--- a/OpenRA.Game/Map/CellLayer.cs
+++ b/OpenRA.Game/Map/CellLayer.cs
@@ -25,6 +25,15 @@ namespace OpenRA
 		public CellLayer(MapGridType gridType, Size size)
 			: base(gridType, size) { }
 
+		public override void Clear()
+		{
+			if (CellEntryChanged != null)
+				throw new InvalidOperationException(
+					"Cannot clear values when there are listeners attached to the CellEntryChanged event.");
+
+			base.Clear();
+		}
+
 		public override void CopyValuesFrom(CellLayerBase<T> anotherLayer)
 		{
 			if (CellEntryChanged != null)
@@ -34,21 +43,6 @@ namespace OpenRA
 			base.CopyValuesFrom(anotherLayer);
 		}
 
-		public static CellLayer<T> CreateInstance(Func<MPos, T> initialCellValueFactory, Size size, MapGridType mapGridType)
-		{
-			var cellLayer = new CellLayer<T>(mapGridType, size);
-			for (var v = 0; v < size.Height; v++)
-			{
-				for (var u = 0; u < size.Width; u++)
-				{
-					var mpos = new MPos(u, v);
-					cellLayer[mpos] = initialCellValueFactory(mpos);
-				}
-			}
-
-			return cellLayer;
-		}
-
 		// Resolve an array index from cell coordinates
 		int Index(CPos cell)
 		{
diff --git a/OpenRA.Game/Map/CellLayerBase.cs b/OpenRA.Game/Map/CellLayerBase.cs
index 42739bd9ca..9d09322f80 100644
--- a/OpenRA.Game/Map/CellLayerBase.cs
+++ b/OpenRA.Game/Map/CellLayerBase.cs
@@ -35,6 +35,11 @@ namespace OpenRA
 			entries = new T[size.Width * size.Height];
 		}
 
+		public virtual void Clear()
+		{
+			Array.Clear(entries, 0, entries.Length);
+		}
+
 		public virtual void CopyValuesFrom(CellLayerBase<T> anotherLayer)
 		{
 			if (Size != anotherLayer.Size || GridType != anotherLayer.GridType)
diff --git a/OpenRA.Mods.Common/Pathfinder/CellInfo.cs b/OpenRA.Mods.Common/Pathfinder/CellInfo.cs
index d0e113b5fd..c336eec65b 100644
--- a/OpenRA.Mods.Common/Pathfinder/CellInfo.cs
+++ b/OpenRA.Mods.Common/Pathfinder/CellInfo.cs
@@ -9,13 +9,15 @@
  */
 #endregion
 
+using System;
+
 namespace OpenRA.Mods.Common.Pathfinder
 {
 	/// <summary>
 	/// Describes the three states that a node in the graph can have.
 	/// Based on A* algorithm specification
 	/// </summary>
-	public enum CellStatus
+	public enum CellStatus : byte
 	{
 		Unvisited,
 		Open,
@@ -23,36 +25,52 @@ namespace OpenRA.Mods.Common.Pathfinder
 	}
 
 	/// <summary>
-	/// Stores information about nodes in the pathfinding graph
+	/// Stores information about nodes in the pathfinding graph.
+	/// The default value of this struct represents an <see cref="CellStatus.Unvisited"/> location.
 	/// </summary>
 	public readonly struct CellInfo
 	{
 		/// <summary>
-		/// The cost to move from the start up to this node
+		/// The cost to move from the start up to this node.
 		/// </summary>
 		public readonly int CostSoFar;
 
 		/// <summary>
-		/// The estimation of how far is the node from our goal
+		/// The estimation of how far this node is from our target.
 		/// </summary>
 		public readonly int EstimatedTotal;
 
 		/// <summary>
-		/// The previous node of this one that follows the shortest path
+		/// The previous node of this one that follows the shortest path.
 		/// </summary>
 		public readonly CPos PreviousPos;
 
 		/// <summary>
-		/// The status of this node
+		/// The status of this node. Accessing other fields is only valid when the status is not <see cref="CellStatus.Unvisited"/>.
 		/// </summary>
 		public readonly CellStatus Status;
 
 		public CellInfo(int costSoFar, int estimatedTotal, CPos previousPos, CellStatus status)
 		{
-			CostSoFar = costSoFar;
-			PreviousPos = previousPos;
+			if (status == CellStatus.Unvisited)
+				throw new ArgumentException(
+					$"The default {nameof(CellInfo)} is the only such {nameof(CellInfo)} allowed for representing an {nameof(CellStatus.Unvisited)} location.",
+					nameof(status));
+
 			Status = status;
+			CostSoFar = costSoFar;
 			EstimatedTotal = estimatedTotal;
+			PreviousPos = previousPos;
+		}
+
+		public override string ToString()
+		{
+			if (Status == CellStatus.Unvisited)
+				return Status.ToString();
+
+			return
+				$"{Status} {nameof(CostSoFar)}={CostSoFar} " +
+				$"{nameof(EstimatedTotal)}={EstimatedTotal} {nameof(PreviousPos)}={PreviousPos}";
 		}
 	}
 }
diff --git a/OpenRA.Mods.Common/Pathfinder/CellInfoLayerPool.cs b/OpenRA.Mods.Common/Pathfinder/CellInfoLayerPool.cs
index 440a1ad3af..b76554747a 100644
--- a/OpenRA.Mods.Common/Pathfinder/CellInfoLayerPool.cs
+++ b/OpenRA.Mods.Common/Pathfinder/CellInfoLayerPool.cs
@@ -11,7 +11,6 @@
 
 using System;
 using System.Collections.Generic;
-using OpenRA.Primitives;
 
 namespace OpenRA.Mods.Common.Pathfinder
 {
@@ -19,15 +18,11 @@ namespace OpenRA.Mods.Common.Pathfinder
 	{
 		const int MaxPoolSize = 4;
 		readonly Stack<CellLayer<CellInfo>> pool = new Stack<CellLayer<CellInfo>>(MaxPoolSize);
-		readonly CellLayer<CellInfo> defaultLayer;
+		readonly Map map;
 
 		public CellInfoLayerPool(Map map)
 		{
-			defaultLayer =
-				CellLayer<CellInfo>.CreateInstance(
-					mpos => new CellInfo(PathGraph.PathCostForInvalidPath, PathGraph.PathCostForInvalidPath, mpos.ToCPos(map), CellStatus.Unvisited),
-					new Size(map.MapSize.X, map.MapSize.Y),
-					map.Grid.Type);
+			this.map = map;
 		}
 
 		public PooledCellInfoLayer Get()
@@ -42,9 +37,14 @@ namespace OpenRA.Mods.Common.Pathfinder
 				if (pool.Count > 0)
 					layer = pool.Pop();
 
+			// As the default value of CellInfo represents an Unvisited location,
+			// we don't need to initialize the values in the layer,
+			// we can just clear them to the defaults.
 			if (layer == null)
-				layer = new CellLayer<CellInfo>(defaultLayer.GridType, defaultLayer.Size);
-			layer.CopyValuesFrom(defaultLayer);
+				layer = new CellLayer<CellInfo>(map);
+			else
+				layer.Clear();
+
 			return layer;
 		}
 
diff --git a/OpenRA.Mods.Common/Pathfinder/PathSearch.cs b/OpenRA.Mods.Common/Pathfinder/PathSearch.cs
index b8f34f903f..08f69a44b8 100644
--- a/OpenRA.Mods.Common/Pathfinder/PathSearch.cs
+++ b/OpenRA.Mods.Common/Pathfinder/PathSearch.cs
@@ -119,7 +119,8 @@ namespace OpenRA.Mods.Common.Pathfinder
 				var neighborCell = Graph[neighborCPos];
 
 				// Cost is even higher; next direction:
-				if (neighborCell.Status == CellStatus.Closed || gCost >= neighborCell.CostSoFar)
+				if (neighborCell.Status == CellStatus.Closed ||
+					(neighborCell.Status == CellStatus.Open && gCost >= neighborCell.CostSoFar))
 					continue;
 
 				// Now we may seriously consider this direction using heuristics. If the cell has