Rapid City or Sun Valley?

Neither place is a beach destination, and in July and August both send swimmers to mountain lakes. Rapid City has a slight edge because Sheridan Lake, Pactola Reservoir and Sylvan Lake lie within about half an hour and get warm enough to swim in comfortably. Sun Valley's best shore, Redfish Lake under the Sawtooths, is an hour away and cold even in midsummer, so its heated outdoor pools are the more reliable place to swim.

Both offer small-town eating, and neither is worth the trip for food alone. Rapid City cooks for the Great Plains, with bison burgers, chislic, Indian tacos on Lakota fry bread, and brewpubs around Main Street.

Ketchum, next to Sun Valley, has more ambitious kitchens for its size, cooking Idaho trout, lamb and elk for a well-off crowd, with patios and a farmers' market in summer. There is little cheap or local food, though, and some kitchens shorten their hours out of season.

Rapid City has more to see, even if most of it is modest: the bronze presidents on the downtown corners, the Journey Museum's account of Black Hills and Lakota history, the Badlands fossils at the School of Mines and the Cold War aircraft by Ellsworth.

Sun Valley's story is narrower. There is the 1936 railroad resort with the first chairlifts, the film-star photographs in the lodge and Hemingway's grave in Ketchum, and together they fill an afternoon at most.

Evenings are early and low-key in both. Rapid City has slightly more choice, with brewpubs, sports bars and country-music bars around Main Street Square. During the Sturgis rally in early August the whole region turns loud and late.

In Sun Valley, going out means après-ski in Ketchum's saloons, wine bars and hotel lounges. These are liveliest on winter weekends, and outside the ski season and midsummer evenings end soon after dinner.

Both are serious bases for the outdoors, but Sun Valley goes further. Bald Mountain has long, steep skiing straight from town, with Nordic tracks and backcountry touring nearby. In summer the same slopes become singletrack, and there is fly fishing on Silver Creek, rafting on the Salmon and the Sawtooths an hour north.

Rapid City's strength is its range of landscapes and wildlife: granite spires, the bison herd in Custer State Park, the long tours at Wind Cave and Jewel Cave, the Badlands and the Mickelson Trail. Its skiing near Lead is small, so winter is not its season.

On day trips, Rapid City is far ahead. Mount Rushmore is half an hour away, and the Crazy Horse Memorial, gold-rush Deadwood, the mammoth bones at Hot Springs and the Minuteman Missile silo fill several days, all by car.

Sun Valley is surrounded by wilderness rather than towns. Hailey's short main street, log-cabin Stanley and Shoshone Falls two hours south are about all there is, and most outings head into the mountains instead.

Rapid City is the stronger family choice, shaped by generations of road-tripping children. There is the reptile park, the drive-through park with bears and wolves, Storybook Island, bison stopping traffic and gold panning, though you should expect long hours in the car.

Sun Valley works well for families who ski, with a separate beginners' hill and a good ski school. Nothing there is made for children, though, rainy days are hard to fill and teenagers who don't ski may find it dull.

Sun Valley is easier without a car, as long as you stay in the resort. Ketchum is walkable, a free bus links the town, the village and the lift bases, and a paved path runs the length of the valley. Hot springs, trailheads and the Sawtooths still need a car.

In Rapid City a car is all but essential, since the city buses do not reach the hills. In return, driving is easy, and roads such as the Needles Highway are a pleasure in their own right.

Neither is worth a shopping trip, and what each sells is quite different. Rapid City has regional crafts: Black Hills gold jewellery with its grape-leaf designs, Lakota quillwork and star quilts, and Western boots and hats. Ketchum's few blocks lean upmarket, with art galleries, cashmere boutiques and very good ski and fly-fishing shops, all at high prices.

Rapid City is much the cheaper of the two. Motels and casual meals are reasonable and many sights are free, though summer and the Sturgis rally week push room prices up and a rental car is unavoidable.

Sun Valley is expensive for everything, from rooms to meals to lift access, and there is almost no budget lodging. Staying further down the valley and coming in spring or autumn helps, but it is never cheap.

Sun Valley has the more memorable performances, but only in summer. The free Sun Valley Music Festival brings a professional orchestra to a pavilion on the lawn by the lodge for several weeks, and star skaters perform on the outdoor rink. Outside summer there is almost nothing.

Rapid City spreads a smaller programme across the year, with the Black Hills Symphony, touring shows at the civic centre and a summer playhouse in Custer State Park. Its most distinctive event is the large autumn powwow.

Sun Valley is the better place to unwind. It has full resort spas, outdoor heated pools that are at their best under falling snow, and rough hot spring pools beside the creek up the Warm Springs valley.

Rapid City offers little in town. Its one real draw is the historic spring-fed pool at Hot Springs, an hour south, which has drawn bathers since the 1890s. Beyond that, rest means a quiet cabin in the hills.