I'll be taking an early morning bus from Puno to Arequipa in February, and will most likely arrive around 12noon. Then I'll be catching a night bus to Nazca, which gives me a few hours to do some sightseeing in AQP. What are the absolute must-sees? I've already noted down Santa Catalina and the plaza area, but where else should I go? Sadly I won't have time to visit the Colca Canyon so that's not an option.
Are there any museums worth a visit? Should I pre-book a tour of the city with an agency, or can I just go it alone? And, where's the best place to stash my pack while I go sightseeing?