Tibet is located on the Tibetan Plateau, which is often referred to as the 'Roof of the World.' The average elevation of Tibet is around 4,000 meters (13,123 feet) above sea level. Some parts of Tibet, such as Mount Everest, can reach elevations of more than 8,000 meters (26,247 feet). Because of the high altitude, visitors to Tibet may experience altitude sickness, which can cause symptoms such as headaches, nausea, and dizziness.