The neighbourhood around the Rialto Market in San Polo, Venice, is a warren of tiny alleys. The arches overhead, with weeds growing out of the cracks, seem to serve no structural purpose. I was told that they signified ownership; if someone owned two adjacent buildings, an arch would be built between them to show that they had the same owner. You often see these arches at the entrance to a small square which, in Renaissance times, often belonged to an extended family. (That also explains the impressive churches found in tiny, out-of-the-way, courtyards.)
The bridge at the end of the Fondamenta Riva Olio (by the Grand Canal) ends at a wall that forms one end of the Pescheria (fish market). In this photo, you can see the arches of the fish market on the left.
If you walk in the colonnade behind the tourist shops of the Rialto Market (yes, the stores with the scarves, souvenir magnets, leather bags, and San Marco banners) and look up, you’ll see these old, unprotected frescos over walls covered with graffiti. The sheer volume of artwork in Venice is staggering. I took these photos in the morning, before the shops had opened, so it wasn’t too crowded.
Detail of fresco and groin-vaulting.