Sadly, this ambitious tree house isn’t available as a holiday home (yet), but it’s certainly worth a mention. It was designed by Gordon Brown, a talented Scottish designer who was asked to create a treehouse in the grounds of a grand estate in Fife for the owner’s children. It’s built in an ancient cedar, it has a tree deck with a dining area, a giant swing, and a zip-wire that “transports the more adventurous over 600 feet to a distant tree”. Nice work, Gordon.