diff --git a/Jumpy.Shared/JumpyGame.cs b/Jumpy.Shared/JumpyGame.cs
index eb4b9a6..36d3474 100644
--- a/Jumpy.Shared/JumpyGame.cs
+++ b/Jumpy.Shared/JumpyGame.cs
@@ -54,6 +54,7 @@ namespace Jumpy {
 
     // Called once per game. Loads all game content.
     protected override void LoadContent() {
+      Console.WriteLine("LoadContent()");
       spriteBatch = new SpriteBatch(GraphicsDevice);
       font = Content.Load<SpriteFont>("font");
       // TODO: decouple things like Player and World from their textures.
@@ -86,6 +87,7 @@ namespace Jumpy {
         display.SetFullScreen(fullScreen);
       }
 
+      List<Rectangle> collisionTargets = world.CollisionTargets();
       player.Update(gameTime, gamePad);
 
       base.Update(gameTime);
@@ -132,6 +134,11 @@ namespace Jumpy {
       // Draw foreground tiles.
       world.Draw(spriteBatch);
 
+      // Draw debug rects.
+      foreach (var rect in world.CollisionTargets()) {
+        DrawRect(spriteBatch, rect, Color.Yellow);
+      }
+
       // Aaaaand we're done.
       spriteBatch.End();
 
diff --git a/Jumpy.Shared/World.cs b/Jumpy.Shared/World.cs
index 9dd61f4..8a363fc 100644
--- a/Jumpy.Shared/World.cs
+++ b/Jumpy.Shared/World.cs
@@ -1,5 +1,6 @@
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Graphics;
+using System;
 using System.Collections.Generic;
 
 namespace Jumpy {
@@ -20,8 +21,8 @@ namespace Jumpy {
       this.position = position;
     }
 
-    public Rectangle Position { get; }
-    public Terrain Terrain { get; }
+    public Rectangle Position { get { return position; } }
+    public Terrain Terrain { get { return terrain; } }
 
     public void Draw(SpriteBatch spriteBatch) {
       int size = World.TileSize;
@@ -84,5 +85,18 @@ namespace Jumpy {
         }
       }
     }
+
+    public List<Rectangle> CollisionTargets() {
+      var result = new List<Rectangle>();
+      for (int j = 0; j < height; j++) {
+        for (int i = 0; i < width; i++) {
+          var t = tiles[i, j];
+          if (t.Terrain != Terrain.Empty) {
+            result.Add(t.Position);
+          }
+        }
+      }
+      return result;
+    }
   }
 }