The Snail House is named after the spiral staircase shape, and you can see most of the scenery of Venice when you go up the steps.
It's easy to find this place by doing some guides in advance (go to Campo Manin, there are signs from there). Tickets worth 5 euros in absolute terms. When we arrived there were a few children running up and down the stairs (without their parents watching), but as soon as they left, it was pleasant and quiet. The stairs are gorgeous and the view from the top. It was foggy when we arrived, which was quite magical. Nice view of the cathedral and bell tower. We stayed there for more than 30 minutes because we didn't want to leave. Take time to visit here! Closed on Monday.