Venice closes early: the night is a giro d'ombra between bacari, a spritz standing in a campo, and a short list of places still serving once the day-trippers have gone.
Giro d'ombra around Rialto
An ombra is a small glass of wine and cicheti are the snacks on the counter; the lanes of San Polo behind the Rialto market hold the densest run of old bacari, and the standard evening is two or three glasses across several of them. Most shut by about 9 or 10pm, so start early.
Campo Santa Margherita
The student square in Dorsoduro and the one place in Venice with a dependable late outdoor crowd, ringed with bars selling cheap spritz. Outdoor tables are cleared well before the crowd is ready to leave, and the drinking moves inside or onto the paving.
Il Mercante
A cocktail bar on Campo dei Frari with a themed, rotating menu, and one of the few places in the historic centre serving properly late. It is walk-in only by policy, so there is nothing to book.
Venice Jazz Club
A small live-music room in Dorsoduro near the Ponte dei Pugni, with sets on scheduled nights through most of the year. Capacity is limited, so book through the club's own site rather than turning up.
Teatro La Fenice
The opera house rebuilt after the 1996 fire, running opera, symphonic and chamber seasons across La Fenice itself and the Teatro Malibran. It also opens for daytime guided visits, and the season calendar and tickets are on its own site.