Shopping is a good thing, to attend to "Zenith's" football match, to visit Hermitagе, Petropavlovskaya fortress, Artillery museum, Kronstadt... - also good, but for Gods sake, do not experiment with local cuisine. This herring with beetroot and mayonnaise, "seledka pod shuboi" as they call this dish, will knock out your gizzard (few years ago, I managed to kick-start my girl friend (in sense - female friend) stomach with greasy cheese burek and yoghurt). Not to mention their soups and porridge... and f.... pickling cucumbers - Russians have some fixation on those.

Stick to the dishes from southern regions - shashlik (skewered meat), shaurma (like giros, minus tzatziki), pirozhki (buns with different fillings), and, of course, Olivier salad.

Kvas is good, tap or bottled - doesn't matter, fine chocolate, chocolate candies too.

Or you can find Italian restaurant...