Inca Trail to Machu Picchu terminus at the Sun Gate on Machu Picchu mountain. The two longer routes require an ascent to beyond above sea level, which can result in altitude sickness. Concern about overuse leading to erosion has led the Peruvian government to place a limit on the number of people who may hike this trail per season, and to sharply limit the companies that can provide guides. As a result, advance booking is mandatory. A maximum of 500 people are allowed on the trail each day, of which only 200 are trekkers, the rest being guides and porters. As a result, the high
Machu Picchu northwest edge of the rock platform points out the Solstice Window to within 2’ of the 15th century June solstice rising Sun. For comparison, the angular diameter of the Sun is 6'. The Inca constellation Qullca, storehouse, can be viewed out the Qullqa Window at sunset during the 15th century June Solstice, hence the window's name. At the same time, the Pleaides are in the opposite end of the sky. Also seen through this window on this night are the constellations Llamacnawin, Llama, Unallamacha, Machacuay, and the star Pachapacariq Chaska (Canopus). The "Intihuatana" stone is one of many ritual stones