As you walk up the Fondamenta Arsenale towards the historic dockyard, there’s a spaciousness that doesn’t exist elsewhere in the city.
Fewer visitors perhaps? It’s very possible; I can’t imagine the average day tripper has this part of Castello on their itinerary.
Less traffic on the Rio de L’Arsenal? Also possible as this canal doesn’t connect to the rest of the network that links the islands of the city.
A broader channel of water? Broader than many certainly, but there are plenty that are just as open.
Then the penny drops; where is the forest of mooring posts that lines the numerous waterways of the city? Is parking discouraged here because of the military base, the lack of mooring posts being akin to painting double yellow lines along a British road? The answer, when I spotted it, is much more simple. Here there is a tidier solution at regular intervals along the fondamenta.