If you're me and spend your leisure time hanging around cathedrals, square is a lovely prompt for cloisters. I adore sitting in these (usually) square courtyards, covered walkways around a central garden. Long since shorn of their monastic use, but still lovely places. This one is Narbonne Cathedral's.
The slight downside to cloisters is you often find it hard to take a shot that really shows they're square... So I append a partial plan of the cathedral with blob of blue identifying the cloister. Definitely square!
It's a lovely place, Narbonne. I was there less than a week ago. *weeps*