in peru when you order a sandwich there are soooo many kinds of condiments to choose from. it's pretty crazy. mostaza (mustard) ketchup (um, ketchup) mayonesa (mayonnaise) aceituna (olive) and aji (spicy peruvian pepper) plus im sure more than i dont know about. 

and, there of course as in any big city, is plenty of graffiti to discover.