For a demo recently I needed to display a map, have pan/zoom controls, add markers and overlays etc etc. Google Maps (or similar) to the rescue right? Not in this case. Unfortunately the place wasn’t real, it was a location within the Battlefield 2 game being used for some simulation of research we were doing. Now I know it’s possible to use something like Google Maps to display my own map tiles etc but it looked complicated and I think I’d have to pretend I was working with real latitude/longitudes etc. Then I stumbled upon OpenLayers. I actually knew about OpenLayers before, as an open-source client-side library for mapping controls. What I didn’t realise was how flexible it was and that I could simply give it a single image and my own coordinate system and then let it do all the rest. This example from the handy list of OpenLayers examples demonstrates how it works in just a few lines of JavaScript. Perfect.