They are small, factory-built cottages (up to 400 square feet, and about 10 feet wide by 40 feet long), made on a trailer-type frame with wheels and perched on a narrow RV-size lot, usually in an RV park or campground. While mobility is a legal must, the only time most are moved is when they are installed onto the campground lot.
Most have full-size bathrooms and kitchen appliances, hardwood floors, and can sleep four to six. Rather like a normal house, but compressed.
While most are found in southern climes frequented by snowbirds, park models are finding their way to RV parks and campgrounds up north.
And for many people, these miniature cottages are replacing traditional vacation cabins in the mountains or on the beach - usually at a lower price, since they're small and you're not buying a full-size lot in what often is an expensive vacation community.
Take the Sneesby family's park-model getaway in Washington state, for example.
The Sneesbys purchased a new park model for about $45,000 delivered. The lot in a private campground overlooking popular Lake Chelan in the central part of the state cost $35,000.
The family put its park model at the edge of a lot next door to one owned by friends, leaving the middle for a mutual barbecue and sitting area.
"We don't travel, and the inside is more like a house than an RV," said David Sneesby. "The lake, the sun - this is just a gorgeous area in summer and for skiing in winter. So we don't need to go elsewhere."
The Sneesbys' park model has all the amenities of home - full kitchen, bath, living/dining room, bedroom, a loft with space for two youngsters, and an outside storage shed.
As you'd imagine, park models vary in style and amenities. And they can be found as rentals in some of the nation's most scenic settings.
At the Spartan end, you might put the park models at the Rolling Huts Campground in Mazama, a small community in the high mountains of central Washington, not far from the Sneesbys' tiny Lake Chelan cottage.
These models, popular in part because of their interesting architecture, consist of rusted metal frames on wheels - for a rustic, Western look - with cork floors, lots of glass for light, wooden cubes that double as tables or stools, small kitchens with a microwave, dishes, a half-size fridge, and sink. There's a wood fireplace, a platform double bed, and a portable potty in a separate enclosure on the deck.
Shipping containers out back are made into common restrooms and showers. A cafe serves breakfast, lunch, and dinner.
The Mazama models lure serious hikers in summer and cross-country skiers in winter. They rent for $135 a night, $145 on holidays.
Many park models, like those in Mazama, are rental units. And some are popular with RV owners and those pulling trailers, who may rent one in a favorite RV park as a way to expand their seasonal living space or to use for entertaining.
Manufacturers of park models are scattered all over the country, and the style and architecture they feature often reflect the region in which the units will be used. Prices range from less than $20,000 to more than $60,000 for new ones; $20,000 is not an uncommon price for used models. Lot leasing goes from $2,000 to $8,000 a year, depending on the location, and usually gives owners land rights and a share of pools and community buildings on the property.
Michael Gast, vice president of communications for Kampgrounds of America, said KOA has more than 2,000 park models for rent at 300 of its 484 campgrounds in the United States and Canada. KOA also leases land to people who would rather own their park model than rent one.
Park models are yet another example of how the needs and demands of senior travelers are influencing the travel market.
And while they often offer more comfort and space than traditional RVs or motor homes, they also present the possibility of an affordable way to experience up close some of the nation's choicest scenic areas.
Information
Search the Internet for "park models" to get a sense of the array of manufacturers and prices, both new and used.
Helpful sites:
Recreation Vehicle Industry Association (RVIA) for information about the industry at www.rvia.com.
Kampgrounds of America at www.koa.com.
National Association of RV Parks and Campgrounds at www.ARVC.org.
And two sites with information about park models in various campgrounds across the country are at www.gocampingamerica.com and www.campjellystone.com
To comment, e-mail TravelTalk@phillynews.com.