Located west of the landmark Rialto Bridge, the district of San Polo centers around the Rialto Market, the most popular area in which to seek out local fish, meat, produce, and tourist curios. The smallest of the Venetian sestiere (boroughs), San Polo nevertheless shines due the aforementioned market and the quality of nightlife and cuisine to be found in its pedestrian streets.
One of many areas that contribute to the romantic mystique of Venice, you'll find numerous contemporary Italian eateries, many with delectable views of the canal. Try Bancogiro for its cicchetti (the Italian version of tapas) and wine selection or head further south to pizza staple, Antico Forno. If you're seeking out potential watering holes, the cichetti and fun atmosphere at Al Merca are great during the evening, while cocktail bar Muro Venezia is a fine choice, day or night.
If you plan on wandering, especially if your intention is to drink, keep a few of these places in mind; otherwise, you may waste a bit of time trying to put a string of establishments together. Unless you've got a wide-open agenda, then getting a little bit lost in Venice may be the best thing to happen to you.