World's Largest tree house

The halcyon days of our youth where a few 2x4s pounded into an old elm with rusty nails constituted the coolest tree house on the block are not just long dead, but now embarrassingly overshadowed by the richest kid on the street, Lord Northumberland, and his World's Largest tree house. 

Located on the grounds of Alnwick Gardens just 95 miles south of Edinburgh (and next to the Alnwick Castle, the very one used in the Harry Potter films), this 6,000-square-foot tree house leviathan soars 56 feet above the groundand is connected with 4,000-square-feet of suspended walkways. It has a restaurant that seats 120 people as well as classrooms, cafes, turrets, wobbly bridges, and imported wood from all over the world. Oh, and it cost $7 million.