Walking through Venice is wonderful.
You never know what you'll see around the next corner,
or from the top of the next bridge.
A while back I was crossing the bridge over the canal known as Rio del Fontego dei Tedeschi, and I saw this sign,
and the gondola activity going on behind it.
This is the canal that feeds into the Canale Grande just north of the Rialto Bridge. The servizio name on the sign is that of the Traghetto di Santa Sofia. They have a large traghetto and stazione across the Grand Canal from the fish market, but this appears to also be part of their service area.