diff --git a/src/ol/tilebounds.js b/src/ol/tilebounds.js
index 04a77a43fe..216ee49e0a 100644
--- a/src/ol/tilebounds.js
+++ b/src/ol/tilebounds.js
@@ -1,28 +1,52 @@
 goog.provide('ol.TileBounds');
 
 goog.require('goog.asserts');
-goog.require('goog.math.Box');
+goog.require('ol.Rectangle');
 goog.require('ol.TileCoord');
 
 
 
 /**
  * @constructor
- * @extends {goog.math.Box}
- * @param {number} top Top.
- * @param {number} right Right.
- * @param {number} bottom Bottom.
- * @param {number} left Left.
+ * @extends {ol.Rectangle}
+ * @param {number} minX Minimum X.
+ * @param {number} minY Minimum Y.
+ * @param {number} maxX Maximum X.
+ * @param {number} maxY Maximum Y.
  */
-ol.TileBounds = function(top, right, bottom, left) {
-
-  goog.asserts.assert(top <= bottom);
-  goog.asserts.assert(left <= right);
-
-  goog.base(this, top, right, bottom, left);
-
+ol.TileBounds = function(minX, minY, maxX, maxY) {
+  goog.base(this, minX, minY, maxX, maxY);
+};
+goog.inherits(ol.TileBounds, ol.Rectangle);
+
+
+/**
+ * @param {...ol.TileCoord} var_args Tile coordinates.
+ * @return {!ol.TileBounds} Bounding tile box.
+ */
+ol.TileBounds.boundingTileBounds = function(var_args) {
+  var tileCoord0 = arguments[0];
+  var tileBounds = new ol.TileBounds(tileCoord0.x, tileCoord0.y,
+                                     tileCoord0.x, tileCoord0.y);
+  var i;
+  for (i = 1; i < arguments.length; ++i) {
+    var tileCoord = arguments[i];
+    goog.asserts.assert(tileCoord.z == tileCoord0.z);
+    tileBounds.minX = Math.min(tileBounds.minX, tileCoord.x);
+    tileBounds.minY = Math.min(tileBounds.minY, tileCoord.y);
+    tileBounds.maxX = Math.max(tileBounds.maxX, tileCoord.x);
+    tileBounds.maxY = Math.max(tileBounds.maxY, tileCoord.y);
+  }
+  return tileBounds;
+};
+
+
+/**
+ * @return {ol.TileBounds} Clone.
+ */
+ol.TileBounds.prototype.clone = function() {
+  return new ol.TileBounds(this.minX, this.minY, this.maxX, this.maxY);
 };
-goog.inherits(ol.TileBounds, goog.math.Box);
 
 
 /**
@@ -34,9 +58,9 @@ goog.inherits(ol.TileBounds, goog.math.Box);
 ol.TileBounds.prototype.forEachTileCoord = function(z, f, opt_obj) {
   var tileCoord = new ol.TileCoord(z, 0, 0);
   var x, y;
-  for (x = this.left; x <= this.right; ++x) {
+  for (x = this.minX; x <= this.maxX; ++x) {
     tileCoord.x = x;
-    for (y = this.top; y <= this.bottom; ++y) {
+    for (y = this.minY; y <= this.maxY; ++y) {
       tileCoord.y = y;
       if (f.call(opt_obj, tileCoord)) {
         return;
@@ -47,24 +71,3 @@ ol.TileBounds.prototype.forEachTileCoord = function(z, f, opt_obj) {
     }
   }
 };
-
-
-/**
- * @param {...ol.TileCoord} var_args Tile coordinates.
- * @return {!ol.TileBounds} Bounding tile box.
- */
-ol.TileBounds.boundingTileBounds = function(var_args) {
-  var tileCoord0 = arguments[0];
-  var tileBounds = new ol.TileBounds(tileCoord0.y, tileCoord0.x,
-                                     tileCoord0.y, tileCoord0.x);
-  var i;
-  for (i = 1; i < arguments.length; ++i) {
-    var tileCoord = arguments[i];
-    goog.asserts.assert(tileCoord.z == tileCoord0.z);
-    tileBounds.top = Math.min(tileBounds.top, tileCoord.y);
-    tileBounds.right = Math.max(tileBounds.right, tileCoord.x);
-    tileBounds.bottom = Math.max(tileBounds.bottom, tileCoord.y);
-    tileBounds.left = Math.min(tileBounds.left, tileCoord.x);
-  }
-  return tileBounds;
-};
diff --git a/src/ol/tilebounds_test.js b/src/ol/tilebounds_test.js
index a07fd785ec..9a877c4c12 100644
--- a/src/ol/tilebounds_test.js
+++ b/src/ol/tilebounds_test.js
@@ -2,34 +2,46 @@ goog.require('goog.testing.jsunit');
 goog.require('ol.TileBounds');
 
 
+function testClone() {
+  var tileBounds = new ol.TileBounds(1, 2, 3, 4);
+  var clonedTileBounds = tileBounds.clone();
+  assertTrue(clonedTileBounds instanceof ol.TileBounds);
+  assertFalse(clonedTileBounds === tileBounds);
+  assertEquals(tileBounds.minX, clonedTileBounds.minX);
+  assertEquals(tileBounds.minY, clonedTileBounds.minY);
+  assertEquals(tileBounds.maxX, clonedTileBounds.maxX);
+  assertEquals(tileBounds.maxY, clonedTileBounds.maxY);
+}
+
+
 function testContainsPositive() {
-  var tb = new ol.TileBounds(0, 2, 2, 0);
-  var tc = new ol.TileCoord(3, 1, 1);
-  assertTrue(tb.contains(tc));
+  var tileBounds = new ol.TileBounds(0, 0, 2, 2);
+  var tileCoord = new ol.TileCoord(3, 1, 1);
+  assertTrue(tileBounds.contains(tileCoord));
 }
 
 
 function testContainsNegative() {
-  var tb = new ol.TileBounds(0, 2, 2, 0);
-  var tc = new ol.TileCoord(3, 1, 3);
-  assertFalse(tb.contains(tc));
+  var tileBounds = new ol.TileBounds(0, 0, 2, 2);
+  var tileCoord = new ol.TileCoord(3, 1, 3);
+  assertFalse(tileBounds.contains(tileCoord));
 }
 
 
 function testBoundingTileBounds() {
-  var tb = new ol.TileBounds.boundingTileBounds(
+  var tileBounds = new ol.TileBounds.boundingTileBounds(
       new ol.TileCoord(3, 1, 3),
       new ol.TileCoord(3, 2, 0));
-  assertEquals(tb.top, 0);
-  assertEquals(tb.right, 2);
-  assertEquals(tb.bottom, 3);
-  assertEquals(tb.left, 1);
+  assertEquals(1, tileBounds.minX);
+  assertEquals(0, tileBounds.minY);
+  assertEquals(2, tileBounds.maxX);
+  assertEquals(3, tileBounds.maxY);
 }
 
 
 function testBoundingTileBoundsMixedZ() {
   assertThrows(function() {
-    var tb = new ol.TileBounds.boundingTileBounds(
+    var tileBounds = new ol.TileBounds.boundingTileBounds(
         new ol.TileCoord(3, 1, 3),
         new ol.TileCoord(4, 2, 0));
   });
@@ -38,7 +50,7 @@ function testBoundingTileBoundsMixedZ() {
 
 function testForEachTileCoord() {
 
-  var tileBounds = new ol.TileBounds(2, 1, 3, 0);
+  var tileBounds = new ol.TileBounds(0, 2, 1, 3);
 
   var tileCoords = [];
   tileBounds.forEachTileCoord(5, function(tileCoord) {