The postmaster stamps a customer's postcards from the world's highest post office located at over 5200 metres (17060 feet), near the base camp of Mount Everest, also known as Qomolangma, in the Tibet Autonomous Region April 29, 2008. The post office services around 30 customers a day, and is only open for seven months of the year between April and October. REUTERS/David Gray (CHINA)