Travelers looking for a vacation in the great outdoors are turning to a nostalgic source of comfort and solitude: treehouses.

But these aren’t the treehouses of their childhood. Like the travelers who are booking them, the treehouses have matured too.

Modern treehouses are more luxury homes than kid hangouts — with a price to match. Treehouses constructed by professionals can easily cost six figures to build.

“A fully appointed treehouse with kitchen, bathroom, heat and air conditioning … we’re building those around $200,000,” Pete Nelson, the star of Animal Planet’s TV show “Treehouse Masters,” told CNBC in 2014.

Treehouses that are built for people to live in now average around $240,000, according to HomeAdvisor, a website that connects homeowners with home services.

Since then, prices have risen along with demand, a situation further propelled by the global pandemic and a desire for offbeat, outdoor accommodations.

Aside from a worn-out patch of grass in the backyard, old-school treehouses didn’t typically incorporate much of an entrance. Modern ones do, some with gated walkways, stone staircases and ramps built for wheelchairs and pets.

One such treehouse is the Chez’ Tree Rest Treehouse in upstate New York, which is accessible via a 60-foot footbridge that begins at a heart-shaped gate. Another 30-foot-long cable bridge connects the treehouse to a separate relaxation deck.

Owner Tom Wallace discusses the treehouse’s construction in a video tour of the treehouse where he also provides tips for a comfortable stay.

Rates start at $285 per night.

Treehouses for children should be between six and 12-feet tall with railings that are at least 36 inches high, according to Tree Top Builders, a custom builder based in Exton, Pennsylvania. Those heights also assume a mulch or wood chips are placed below the treehouse to soften a potential fall.  

Treehouses built for big people aren’t constrained by these standards, as evidenced by the three-story Punta Jaguar jungle treehouse in Matapalo, Costa Rica.

What the house lacks in walls, it makes up in style. Sinks and water faucets are made of seashells, and a separate ground-level bungalow comes with colorful swivel windows and electric drawbridge-style dropdown decks. It has a caretaker and private path to the beach, according to the website. Guests are encouraged to be 7 years old and above.

Rates start at $255 per night.

Thrill-seekers can sleep in the Amazon rainforest at Peru’s Inkaterra Reserva Amazonica ecolodge. The lodge’s sole treehouse is located more than 70 feet above the rainforest floor at the end of a series of seven suspended bridges.

Programs start from $492 for a two-night stay, plus an additional $660 to sleep in the treehouse.

Childhood treehouses may have granted views of neighbors’ backyards, but nothing as spectacular as Australia’s Blue Mountains.

A tongue-in-cheek sign on the Secret Treehouse‘s door may say that no grown-ups are allowed, but in reality, it’s the kids who can’t come along. This treehouse is built on tall stilts at a high elevation and has a combination bridge and ladder entrance.

Rates start at 1,095 Australian dollars ($804) for a one-night stay.

Sports pennants and sticker-adorned walls have been sidelined for plush interiors that resemble modern homes.

This is evident at the Treeful Treehouse Sustainable Resort in Okinawa, Japan. All bookings include two treehouses: the earthy Spiral Treehouse which comes with hammocks and yoga mats, and the luxurious Aerohouse, which has the look and feel of a five-star hotel suite. Its muted, sophisticated décor comes with creature comforts such as an espresso machine and wine cellar, according to the website.

The treehouse resort has been open for less than a month. Guests can currently book two-night stays — no more, no less — and all travelers must be 10 years old and above.

Rates are 100,000 Japanese yen ($905) per night for up to three people; a fourth person is an extra $225 per night. Bookings are currently 33% off the regular rates. 

While cooking and treehouses once rarely meshed, treehouses now come with full kitchens outfitted with Nespresso coffee machines and kitchen islands.

The two-bedroom Trinity Treehouse near Atlanta has a kitchen that travelers may envy for their homes, let alone their yards. Three sizable windows enlarge the space, which includes an L-shaped countertop, wine rack and breakfast counter for coffee or quick meals. A decorative backsplash sits above the kitchen cabinets, which were made in the host’s woodworking shop, according to the website listing.

Trinity Treehouse is next to the hiking and bike trails of Georgia’s 2,500-acre Davidson-Arabia Mountain Nature Preserve. 

Rates start at $289 per night.

Luxury treehouses needn’t be too serious — that’s what log cabins are for. What distinguishes a treehouse from an elevated house in the woods can be the latter’s dedication to whimsy and childlike fun.

To enter one tropical treehouse on Hawaii’s Big Island, guests climb a ladder to a trapdoor that opens to the second story. Bags and suitcases take a different route; they’re hoisted up via a pulley system.

The Wanderlust Treehouse in Crane Hill, Alabama, doesn’t allow kids, but that didn’t stop its owner from installing a playground-style suspension bridge to connect two parts of the house. The treehouse, which has received perfect scores in all of its 85 Airbnb reviews, has outdoor side-by-side showers, a swinging bed and a fire pit.

Rates start at $350 per night.

Guest who stay at the Loire Valley Lodges have daily breakfast baskets delivered to their doors. They also have access to an onsite restaurant and room service.

The French treehouse hotel opened in July 2020, with the interiors of each of its 18 structures designed by a different contemporary artist.

Rates start at 395 euros ($428) per night.

*Rates are accurate as of publication date.