Spend one extra night, or a 'rest day,' around the villages of Manang and Bhraka to avoid severe altitude sickness while trekking the Annapurna Circuit. The communities are just over 3000 meters above sea level, and staying here allows your body to acclimate to the high altitude. Several side treks, such as a trek up to the Ice Lake or a visit to a huge monastery, can be explored on this rest day. Manang village is also the starting point for the side trip to Tilicho Lake. Only sleep roughly 500 meters higher than where you slept the night before. Although it is beneficial to acclimate by hiking to high altitudes (trek high), you must descend to no more than 500 meters above your last stop to spend the night (sleep low).