This teahouse at the top of Mount Hua’s most remote southern peak – part of the Qinling mountain range just outside of Xi’an, China – takes the concept of high tea to the next level. Built inside a 1,000-year-old Taoist temple, the teahouse sits 7,087 feet (2,160m) above sea level and is accessed by a path known as the Heavenly Stairs. It’s a steep and treacherous climb; at one point, the steps vanish entirely, leaving only narrow strips of wood to navigate, which then reduce to a couple of foot pegs and a chain. That doesn't stop one million people visiting every year, though. Look out for the porters carrying food and water up.