Gradient Elevation Mapping

Moscow Hills is a very pretty map of Moscow, using gradient colored roads to show elevation levels throughout the city. As well as using the color of the roads as a guide you can mouse-over any point on a road to view the elevation at that point.

The colors of the roads don't seem to be generated dynamically on the map. I think the colors are actually present in the map tiles. Theoretically you could create a similar map using the Google Maps API and the Elevation Service. In fact it should be fairly simple to draw a gradient polyline along a road using the Stroke Style feature with the Google Maps SDK for iOS.

It's kind of indicative of Google's current neglect for the Google Maps JavaScript API that gradient polylines have been introduced in the Google Maps SDK for iOS but aren't available in the Maps JavaScript API