The map you were just viewing is a simplified map interface that I wrote for use on my flip phone, which uses an old browser that doesn't understand modern Javascript. It uses map tiles from OpenStreetMap, which is a crowdsourced map data project.

I've set up keybindings so that 2, 4, 6, and 8 will pan north, west, east, and south, and 3 and 9 will zoom in and out, respectively. (Remember to switch to numeric input. You may also need to focus into the page.) With a regular keyboard, the arrow keys and plus/minus will behave as expected.

You can also just focus a button and activate it using the keyboard if your user agent doesn't produce the right kind of keyboard events.