Original poster is Blockhead Dan. He said:

It's closer up to Broadway. There's a small playground just on the Winter Hill side of the tracks with a permanently painted read and blue four-square square. The square's a little small. Somerville seems to have a plethora of permanently painted squares. Perhaps there's some native ringers out there who would put us to shame. Well, us except maybe Jason.

[Officially its known as Sullivan-Hoyt Park on Central Street.]

-Dan