TimberStone Adventures Treehouse. A beautiful 1200 sq. ft. treehouse with a fully equipped kitchen and dinning area, 2 baths with a jacuzzi tub, and enough room to sleep 10 people! A warm and welcoming feeling is created with wooden interior details and handcrafted furniture. Built in a 50 acres forest area by the White Mountains, the treehouse resort with an 18 hole disc golf will be opening later in the summer of 2015. Located in Stoneham, Maine.