Boulder or Scottsdale?

Neither city is anywhere near the sea, so swimming in either means something smaller. Both have summer tubing, on Boulder Creek or the lower Salt River. In Boulder the main alternative is the small sandy swim area at Boulder Reservoir. In Scottsdale the resort pool is the centre of the day, and Saguaro and Canyon Lakes add coves and boat hire within an hour's drive.

The two eat about equally well, in very different styles. Boulder cooks seasonal and health-minded food: Front Range produce, a lot of vegetarian dishes, good bakeries, a Saturday market beside the creek, taprooms across the east side and tea in the carved Tajik pavilion of the Dushanbe Teahouse.

Scottsdale feeds golfers and groups, with steakhouses, patio grills, sushi, long brunches and happy hours. Its most local flavour is Sonoran Mexican, with carne asada and huge flour tortillas. In both places the deeper and more interesting tables are in the big neighbouring city, Denver or Phoenix.

Scottsdale has more to see. Taliesin West, Frank Lloyd Wright's desert studio and part of a UNESCO listing, is a sight worth travelling for. The Museum of the West and the gallery district add to it, and the Heard Museum and the Musical Instrument Museum are a short drive away.

Boulder's appeal lies in setting more than in sights: the wooden Chautauqua colony under the Flatirons, the sandstone and red-tile university campus and I.M. Pei's laboratory on the mesa. A single day covers it.

Boulder goes to bed early. Evenings mean brewery taprooms and cocktail bars around Pearl Street, or the student bars on University Hill, which are loud during term and quiet in summer, and many people are already thinking about a dawn start on the trails. There are barely any clubs, so a serious night out means the trip to Denver.

Scottsdale is the place for a big night. Old Town's few blocks of rooftop lounges, dance clubs and patio bars fill up on Friday and Saturday, and in spring with the baseball crowds and bachelor and bachelorette groups. Expect dress codes, bottle service and noise until the bars close. Away from that pocket, evenings are quiet and spent at the resort.

This is where Boulder pulls well ahead. Over 200km of trails start at the edge of town, Eldorado Canyon is one of the country's great climbing walls, cyclists train at altitude on the canyon roads, and the Indian Peaks and Rocky Mountain National Park are close enough for a day. The landscape also changes through the year, from summer storms to gold aspens in autumn.

Scottsdale's desert is beautiful in its own way, with saguaro and granite boulders in the McDowell Sonoran Preserve and short climbs up Camelback and Pinnacle Peak. But the summer heat restricts hiking to dawn for a third of the year.

The two are about level here, but the outings differ. Boulder's are close and modest: Denver is an easy express-bus ride, and Golden, Fort Collins and the old silver towns of Georgetown and Idaho Springs need a car but not a long drive.

Scottsdale's best trips take longer, with more dramatic scenery: Sedona's red rock, the cliff dwelling at Montezuma Castle and hillside Jerome are around two hours north, and the Grand Canyon is really an overnight.

Both work well with children, in different ways. Boulder is an outdoor town for families, with the creek path, gentle trails, tubing, street performers on Pearl Street and a planetarium for rainy hours. Its zoo and aquarium are in Denver, and the altitude calls for water and hats.

Scottsdale centres on the resort, with lazy rivers, water slides and kids' clubs. The railroad park, the aquarium and Butterfly Wonderland are close by. Every outing needs a car, and the summer heat keeps children indoors from midday.

Boulder is much easier without a car. Downtown, the university and Chautauqua are all a walk or short bike ride apart, linked by off-street paths along the creek, and an express bus runs to Denver. You only need a hire car for trailheads and parks beyond town.

Scottsdale is long, narrow and built for driving, and the light rail does not reach it. A free trolley serves Old Town and the shops, but resorts, the preserve and the airport all mean a car or ride-hailing.

Scottsdale is the better place to shop. A big luxury mall has the fashion houses and department stores, and the Old Town galleries and dealers sell turquoise jewellery, Pueblo pottery and cowboy boots of real quality, though the feel is polished rather than local.

Boulder's Pearl Street Mall is pleasant for independent bookshops and boutiques, and its climbing, running and camping shops are excellent. Beyond that, there isn't much.

Neither is cheap, but Scottsdale gives a careful budget more room. Its resorts cut rates sharply in the hot summer, and motels along the main roads and plenty of casual Mexican food help year-round.

Boulder has few hotels, and rooms are dear, especially in summer and on university weekends. The usual saving is to stay in Denver and drive in. In both, the hiking costs almost nothing.

The two are close here, but their calendars peak at opposite times. Boulder is strongest in summer and in roots music: rock and bluegrass in small rooms most nights, the Colorado Music Festival in the wooden Chautauqua Auditorium, outdoor Shakespeare on campus, and Red Rocks Amphitheatre within reach.

Scottsdale's best season is winter, and it leans on Phoenix: the symphony, opera and ballet are half an hour away, Gammage hosts Broadway tours, and the instrument museum's theatre books world music.

In Boulder, looking after yourself is part of ordinary local life rather than something you book. Classes, bodywork and quiet contemplative practice run through the town, and much of the restoration comes from unhurried mornings and a walk before the day starts. Water is the weak point. In summer there is a cool, spring-fed pool at Eldorado Springs just south of town, and for proper hot soaking you have to drive about an hour to Idaho Springs.

Scottsdale goes further, because comfort is what its resorts are built to sell. Many are planned around the spa, so a whole day can go on treatments, a shaded lounger, golf and a long lunch without getting in the car. Neither city has a public bathing tradition, but Scottsdale makes up for it with private luxury, which is polished and costly.