When to Go
Cusco's high season is June through early September (winter in the southern hemisphere) and the days around the Christmas and Easter holidays. Winter means drier weather and easier traveling but higher lodging prices and larger crowds. Prices and visitor numbers drop dramatically during the November-through-March summer rainy season, except around the holidays.
The Sacred Valley has increasingly taken on a dual personality, depending on the time of day, day of the week, and month of the year. Blame it on Pisac and its famous market. Every Cusco travel agency offers a day tour of the Sacred Valley, with emphasis on Tuesday, Thursday, and Sunday to coincide with the town's larger market days, and they all seem to follow the same schedule: morning shopping in Pisac, buffet lunch in Urubamba, afternoon browsing in Ollantaytambo. You can almost always sign up for one of these tours at the last minute—even early on the morning of the tour—especially if you're here in the September-to-May off-season. Note that the best guides are used for private tours and often get booked up far in advance. On nonmarket days and during the off-season, however, Pisac and the rest of the Sacred Valley are quieter. In any case, the valley deserves more than a rushed day tour if you have the time.