The Yak-a symbol of Tibet-is often considered a messenger of the gods that live in high places. Domesticated over 5,000 years ago, yaks can climb as high as 20,000 feet and survive in temperatures as low as - 40 degrees Celsius. Yak butter tea-made from tea leaves, yak butter and salt-is a traditional Tibetan drink served to guests. Every household served me yak butter tea. It is definitely an acquired taste.