Crossville, Tennessee, hosts what is maybe the largest treehouse in the world! The house rises 97 feet into the sky! The support for the treehouse is provided by a live 80-foot-tall white oak 12 feet in diameter at its base. Six other trees help to support the house too. The treehouse has 10 floors, averaging nine to eleven ft. in height. It was built by Horace Burgess. He says that he has never measured its size, but estimates it to be about 8,000 to 10,000 square feet. He has though (I don’t know why) counted the number of nails he used which is around 258,000. Burgess said that most of his materials are recycled pieces of lumber from garages, storage sheds and barns. Burgess said that he thinks he has sunk about $12,000 into the project. He 'claims' that it is the world’s largest treehouse. It’s just impressive!