Skip the hotel, stay in a horse

Three sites specialise in finding alternative accommodations around the world, including a giant Trojan horse in Belgium, a former radar tower in Panama and a desert cave in Australia.

A family-size tree house in French wine country; an igloo in the Swiss Alps; a hotel located 21ft under the sea in Florida – chances are you won’t find these holiday accommodations on your favourite online booking site.

Instead, a few out-of-the-ordinary lodging websites – Canopy and Stars, Unusual Hotels of the World and Welcome Beyond – have cornered the market in alternative, independently owned accommodations that are sure to make any vacation more memorable, such as a desert cave hotel in Australia, a modernist-style houseboat in Berlin or a former radar tower converted into a bird-watching station in Panama.

Plus these sites don’t charge membership fees; they list more than merely boutique or “design” hotels; they cover broad geographic areas with varied types of structures; and they only list private properties (instead of home stays, where the owners are typically in the room next door).

Canopy and Stars
Begun in 2010, this UK-based site is overseen by Toby Sawday, son of travel guide publisher Alistair Sawday. Its listings emphasise places for “glamping” (glamorous camping) – which could even mean staying in a spacious, air-conditioned tree house. The site’s 265 listings are limited to Britain, Spain, France and Portugal and are dominated by tree houses, yurts and cabins. Yet it also provides about 35 eye-popping accommodations, including a model of a Hobbit house on Cornwall’s coast and an Airstream trailer in Bordeaux.

Welcome Beyond
Castles, design hotels and villa rentals make up most of the listings on this Berlin-based website, which includes about 137 properties in more than 37 countries. Users can use a map or a drop-down menu to search by categories, such as “unusual destinations” and “food and drink”, with about 25 truly off-the-radar finds, including igloos in Switzerland and Germany and a hotel in an ancient cave in the Italian village of Matera.

Unusual Hotels of the World
Listing 315 properties around the world, this site has the deepest selection of the group, including such borderline weird places as a giant Trojan horse in Belgium, a converted jail in southwestern Australia and a Bauhaus-style motel on a disused airfield outside Stuttgart where all of the beds are set inside vintage Mercedes, Porsches and other classic cars. About half of the site’s listings are of comparatively normal (yet still distinctive) properties, such as a pagoda-tower made of cypress wood in a Kenyan wildlife sanctuary.

Sean O’Neill is the travel tech columnist for BBC Travel