World's Best Treehouse Hotels

Why It’s Unique: Located on 22 acres of parkland designed by Frederick Law Olmsted, the two-story Aviary treehouse in the Berkshire Mountains features limestone wet room with an antique soaking tub, circular stairs leading to the second-floor sleeping quarters, and a Bang & Olufsen entertainment system.

Access: Ground-floor entrance.

What to Do: Sample the season’s bounty in Wheatleigh’s elegant Dining Room restaurant, or poke around the historic area’s local galleries, antique shops, and museums.