This is one of those attractions you cant miss in your lifetime. Salar de Uyuni (or Salar de Tunupa) is the world's largest salt flat at 10,582 square kilometers (4,086 sq mi). These salt flats are the largest on earth- marveled at by Neil Armstrong from the moon space vehicle all those years ago. As it dries out, a thick layer of salt transformes this unique place in the world. It has to be seen to be believed!