When to Go
Machu Picchu is open year-round. The Inca Trail is closed every February for maintenance, but Machu Picchu itself is accessible daily, from 6:00am until 5:30pm.
The rainy season in the cloud forest is from typically November to March. Between December and February, you are guaranteed a very wet day at Machu Picchu, so be sure to bring rain gear. But even during the dry season, from June-September, sporadic rain showers are common. So bring a light rain jacket just in case.
June to August is the peak travel time, when many North Americans take their vacations, and hotels and entrance tickets can be booked well in advance. So if you plan to take your Machu Picchu Peru tour during these months, be sure to make your travel arrangements early.