diff --git a/Sources/Voxelotl/ChunkGeneration.swift b/Sources/Voxelotl/ChunkGeneration.swift
index c3467cc..aa9267a 100644
--- a/Sources/Voxelotl/ChunkGeneration.swift
+++ b/Sources/Voxelotl/ChunkGeneration.swift
@@ -14,12 +14,17 @@ public struct ChunkGeneration {
     self.queue.qualityOfService = .userInitiated
   }
 
-  public mutating func generate(chunkID: SIMD3<Int>) {
-    if !generatingChunkSet.insert(chunkID).inserted {
-      return
-    }
+  public mutating func cancelAndClearAll() {
+    self.queue.cancelAllOperations()
+    self.queue.waitUntilAllOperationsAreFinished()
+    self.localReadyChunks.removeAll()
+    self.generatingChunkSet.removeAll()
+  }
 
-    self.queueGenerateJob(chunkID: chunkID)
+  public mutating func generate(chunkID: SIMD3<Int>) {
+    if generatingChunkSet.insert(chunkID).inserted {
+      self.queueGenerateJob(chunkID: chunkID)
+    }
   }
 
   func queueGenerateJob(chunkID: SIMD3<Int>) {
diff --git a/Sources/Voxelotl/Common/ConcurrentDictionary.swift b/Sources/Voxelotl/Common/ConcurrentDictionary.swift
index f61062b..7bf480a 100644
--- a/Sources/Voxelotl/Common/ConcurrentDictionary.swift
+++ b/Sources/Voxelotl/Common/ConcurrentDictionary.swift
@@ -70,6 +70,12 @@ public class ConcurrentDictionary<V: Hashable, T>: Collection {
     }
   }
 
+  public func removeAll(keepingCapacity keep: Bool = false) {
+    self.locked {
+      self.inner.removeAll(keepingCapacity: keep)
+    }
+  }
+
   fileprivate func locked<X>(_ perform: () -> X) -> X {
     self.lock.lock()
     defer {
diff --git a/Sources/Voxelotl/Game.swift b/Sources/Voxelotl/Game.swift
index ab51996..6b56126 100644
--- a/Sources/Voxelotl/Game.swift
+++ b/Sources/Voxelotl/Game.swift
@@ -32,6 +32,8 @@ class Game: GameDelegate {
   }
 
   private func generateWorld() {
+    self.world.removeAllChunks()
+    self.renderChunks.removeAll()
     let seed = UInt64(Arc4Random.instance.next()) | UInt64(Arc4Random.instance.next()) << 32
     printErr(seed)
 #if DEBUG
diff --git a/Sources/Voxelotl/World.swift b/Sources/Voxelotl/World.swift
index 7828e78..214154c 100644
--- a/Sources/Voxelotl/World.swift
+++ b/Sources/Voxelotl/World.swift
@@ -68,6 +68,11 @@ public class World {
     }
   }
 
+  func removeAllChunks() {
+    self._chunkGeneration.cancelAndClearAll()
+    self._chunks.removeAll()
+  }
+
   func generate(width: Int, height: Int, depth: Int, seed: UInt64) {
     self._generator.reset(seed: seed)
     let orig = SIMD3(width, height, depth) / 2