diff --git a/src/map/anim/Map.ZoomPan.js b/src/map/anim/Map.ZoomPan.js
index 75986ccc..9c2c7be8 100644
--- a/src/map/anim/Map.ZoomPan.js
+++ b/src/map/anim/Map.ZoomPan.js
@@ -1,24 +1,52 @@
 
 L.Map.include({
 	zoomPanTo: function (center, targetZoom) {
-		var start = +new Date(),
-		    duration = 1000,
-		    from = this.project(this.getCenter()),
-		    offset = this.project(center).subtract(from);
+
+		var V = 3,
+		    rho = 1.42,
+		    rho2 = rho * rho;
+
+		function sinh(n) { return (Math.exp(n) - Math.exp(-n)) / 2; }
+		function cosh(n) { return (Math.exp(n) + Math.exp(-n)) / 2; }
+		function tanh(n) { return sinh(n) / cosh(n); }
+
+		var from = this.project(this.getCenter()),
+		    to = this.project(center),
+		    offset = to.subtract(from),
+		    u1 = to.distanceTo(from),
+		    size = this.getSize(),
+		    w0 = Math.max(size.x, size.y),
+		    w1 = w0 * this.getZoomScale(this._zoom) / this.getZoomScale(targetZoom);
+
+		function r(i) {
+			var b = (w1 * w1 - w0 * w0 + (i ? -1 : 1) * rho2 * rho2 * u1 * u1) / (2 * (i ? w1 : w0) * rho2 * u1);
+			return Math.log(Math.sqrt(b * b + 1) - b);
+		}
+
+		var r0 = r(0),
+		    S = (r(1) - r0) / rho;
+
+		function w(s) { return w0 * cosh(r0) / cosh(r0 + rho * s); }
+		function u(s) { return w0 * (cosh(r0) * tanh(r0 + rho * s) - sinh(r0)) / rho2; }
+
+		var duration = 1000 * S / V;
 
 		this.fire('zoomstart');
 
 		function step(t) {
-			var center = this.unproject(from.add(offset.multiplyBy(t))),
-				zoom = this._zoom + t * (targetZoom - this._zoom);
+			var s = t * S,
+			    zoom = this.getScaleZoom(this.getZoomScale(this._zoom) * w0 / w(s)),
+			    center = this.unproject(from.add(offset.multiplyBy(u(s) / u1)));
 
 			this._animateZoom(center, zoom);
 		}
 
+		var start = +new Date();
+
 		function frame() {
 			var t = ((+new Date()) - start) / duration; // linear easing
 
-			if (t < 1) {
+			if (t <= 1) {
 				step.call(this, t);
 				L.Util.requestAnimFrame(frame, this);
 			} else {
@@ -27,6 +55,6 @@ L.Map.include({
 			}
 		}
 
-		L.Util.requestAnimFrame(frame, this);
+		frame.call(this);
 	}
 });