Each station is represented by a yellow or a blue dot with a number indicating how the walk goes.
I store 10 digits of pi in each of these stations. Yellow dots are the stations where I have already stored digits, and the blue dots are still unused.
The city is Stockholm. Read my blog for more information.
You can drag the picture around to navigate, and you can also zoom in and out with the tool at the bottom or by double clicking left mouse button for zooming in and right button for zooming out.
The webservice that I use for this has recently changed their technique a bit, which restricts me to show only one chunk of 10 stations at a time. I am planing to make it possible to select chunk with this listbox so that you can see any chunk you want. But it will take a while before I have that ready, so right now only the first chunk (Chunk 0) can be seen.