Best Adults-Only Hotels in the United States

The 39-room Post Ranch Inn is one of the most beautiful hotels in the United States -- if not the entire world -- and offers a romantic, intimate stay (for those 18 and over) amid gorgeous natural surroundings. The hotel is built into the cliffs of Big Sur, and the organic architecture is breathtaking, as are the spacious, eco-sensitive rooms with ocean or mountain views. Rooms also have wood-burning fireplaces, radiant floor heating, outdoor showers or hot tubs, private decks, and organic bath products and linens -- but no televisions or alarm clocks as the hotel strives for a peaceful environment. The award-winning spa focuses on rejuvenating services and even has a shaman on-site; the hotel's clifftop pools are stunning; and free amenities (such as yoga and stargazing) are abundant.

Despite its intimate size (with just 50 rooms), thus luxurious inn has all the amenities of a larger resort: a 7,000-square-foot luxury spa, a lovely pool, and a Michelin-star restaurant. Views of the surrounding countryside are phenomenal, the grounds are lush and peaceful (thanks, in part, to a "no children under 16" policy), and the homey rooms all come with huge terraces (and, in most, fireplaces and soaking tubs). It's a truly special, romantic retreat, and it's location in Rutherford is convenient for exploring Napa Valley.

As a four-pearl property, Austin's Travaasa can't quite compete with the likes of Post Ranch Inn and Auberge du Soleil (both five-pearl hotels). But it nonetheless comes in at number three on our list, and not just for its peaceful atmosphere achieved through its gorgeous setting amid forested hills of the Balcones Canyonlands Preserve, and no-children policy. Its 72 rooms are housed in seven buildings and offer private balconies with beautiful canyon or garden views. Hiking trails, an infinity-edge pool enclosed by a wooden deck, and a luxurious spa are just some of the amenities here, and there's a restaurant serving organic, local fare, with many of the ingredients used sourced from the hotel's own farm.

The 19-room La Mer Hotel and Dewey House is an upscale, adults-only property built at the turn of the century on South Beach. Despite its size, this bed-and-breakfast offers extras such as fitness center access, spa treatments, multiple pools and bars, and beachfront yoga (for a fee) thanks to its proximity to a sister hotel (which does allow children). Guest rooms are beautifully decorated in a classic style, and have flat-screen TVs, mini-fridges, and coffeemakers; some open to balconies. The property serves free breakfast, along with occasional treats like chocolate-covered strawberries -- although this all comes at the cost of a resort fee.

With just six rooms arranged around a beautiful common area that’s all decked out in lavish Balinese-style decor, Ho'oilo House is about as opposite of a generic mega-resort as you can get. The adults-only bed-and-breakfast offers an intimate, romantic alternative to busy chain hotels. Note that amenities are limited to a great continental breakfast and a small, lovely pool, but the experience here less about action and more about relaxing and enjoying the great views of the ocean below.

Canyon Ranch is a health spa and all-inclusive resort in north Tucson near the Santa Catalina Mountains. Here the focus is on wellness, nutrition, and fitness so it makes sense that it's an adults-only property; while children over 14 can stay here, guests must be 18 to participate in various programs, so very few families bring their teens. Daily fitness classes along with informational lectures and a menu packed with healthy, low-calorie food help guests to jumpstart (or maintain) a healthy lifestyle. The color palette of the southwest inspired the decor of the rooms, which come complete with flat-screen TVs, free Wi-Fi, and iPod docks. Immaculate, peaceful grounds and focused spa treatments all provide an incredibly relaxing environment. It offers more amenities than both Ho'oilo House and La Mer Hotel, but its larger size (180 rooms) means it's slightly less intimate, and thereby comes in sixth on our list.

Vintro Hotel South Beach is an upscale Art Deco boutique hotel for the 18-and-up crowd looking for a hip scene. The 50 guest rooms have retro furnishings in citrus tones, and feature flat-screen TVs, Illy espresso machines, and rainfall showerheads. It offers quite a few amenities to lure travelers: vouchers for beach chairs and towels; a rooftop plunge pool; on-site fine dining restaurant; lobby bar; free bicycles; and free Wi-Fi.

The Mermaid & The Alligator is a nine-room upscale bed-and-breakfast housed inside a historic Victorian estate; children under 16 are not permitted. The owners have taken great care to renovate the home with bold and vibrant decor and updated furnishings, and some rooms include romantic perks like deep soaking tubs. Located on Truman Street, three blocks from popular Duval Street, the home is a quiet and peaceful area that is steps from the heart of the entertainment district. There is a lush interior garden with hammock, lounge chairs, and plunge pool, but note that there are no on-site restaurants for lunch and dinner.

Deep in the Poconos, The Lodge at Woodloch is an upscale adult-only retreat where the focus is on the spa. It has all the usual perks of an all-inclusive resort in the region, with acres of woodland, a private lake, and an adjacent golf club, but the restaurant here is a grown-up, farm-to-table affair with some of its produce sourced from its own garden. Guests can spring for chef-curated dinners, with cocktails and a wine list worth exploring. Rooms are quite as luxe as those in the properties mentioned above, but perks like an 18-hole golf course nearby and an indoor pool with heated waterfall features make it a great adults-only pick in the U.S.

For those looking for a more party-centric adults-only atmosphere than one focused on serenity, The Standard Miami is a solid option. It may be about a mile from the beach, and rooms are both small and generic, but here guests enjoy perks like a renowned spa, a massive 24-hour pool with hot tubs, two popular lounges, and a juice bar. Plus, for a small fee, guests can select the "standard time" option, which means you can check in and check out whenever you want throughout the day.