Los Angeles or Phoenix?

This is the widest gap between the two. Los Angeles has more than 100km of shoreline, from the coves of Malibu through Santa Monica and Venice to the South Bay, with surf breaks, volleyball and a bike path along the sand. The water is cool, so people tend to wade and surf rather than swim far.

Phoenix has no coast at all. Swimming there means a resort pool, a day at Saguaro Lake or Canyon Lake, or tubing down the lower Salt River in summer. That is fun, but it does not replace a day at the sea.

Los Angeles is one of America's great places to eat, and its range is the point. You can go from Eastside taco trucks and Koreatown charcoal barbecue to regional Chinese cooking in the San Gabriel Valley, with Thai Town and Little Ethiopia to explore as well. You will drive between them, but each trip is worth it.

Phoenix is narrower and more regional. Its strength is Sonoran cooking: carne asada, paper-thin flour tortillas and bacon-wrapped hot dogs from evening carts, along with good wood-fired pizza. Beyond that it is solid rather than memorable, with Scottsdale's steakhouses covering the polished end.

Neither city has an old quarter to wander, so in both you drive from museum to museum. Los Angeles has far more of them, and bigger names: the Getty Center and Getty Villa, LACMA, the Broad and the Huntington. Hollywood's old movie palaces and the Disney Concert Hall add architecture and screen history.

In Phoenix the highlight is the Heard Museum's Native American collection, with the Musical Instrument Museum and Taliesin West close behind. Together they fill two or three good days, not a week.

Los Angeles has more nights out, and more kinds of them: Hollywood clubs with guest lists, West Hollywood's gay strip, rooftop and cocktail bars downtown and the dive bars of Silver Lake and Echo Park. Phoenix is loud in one place rather than broad. The action centres on the weekend crowds of Old Town Scottsdale, with student bars on Tempe's Mill Avenue and a quieter craft-beer scene around Roosevelt Row.

Both cities close their bars at 2am, and in both you pick one district and get a ride home. In Phoenix, summer heat pushes the evening onto misted patios and into resort pool parties.

Both have wild country close by, but of different kinds. Los Angeles has quick hikes in Griffith Park and Runyon Canyon, the Santa Monica Mountains running down to the sea and the San Gabriels rising above 3,000m with pine forest and winter snow. The ocean adds surfing, kayaking and winter whale watching, and that mix of mountains and coast gives it the edge.

Phoenix is pure Sonoran desert: scrambles up Camelback and Piestewa Peak, South Mountain and the saguaro forest of the McDowell Sonoran Preserve, with Sedona's red rock two hours north. It is superb from October to April, but in summer hiking after mid-morning is dangerous.

Los Angeles has the stronger short list. Santa Barbara, with its mission and red-tile streets, and Catalina Island by ferry are the easy highlights. Laguna Beach, Ojai and the Temecula wineries make good alternatives, though traffic can stretch any drive.

From Phoenix the distances are longer and the destinations more Western in character: the hillside mining town of Jerome, the Montezuma Castle cliff dwelling, Sedona's red rocks, and Tucson with its adobe barrios and Mission San Xavier del Bac. The Grand Canyon is tempting but too far for a comfortable day.

Children are spoilt for choice in Los Angeles. Disneyland, Universal Studios and Knott's Berry Farm sit alongside the space shuttle at the California Science Center, the fossils of the La Brea Tar Pits and the Aquarium of the Pacific. The beaches and mild weather make any month workable.

Phoenix covers the basics with its zoo, science centre, children's museum and water parks, and spring training baseball makes an easy outing in March. Its limit is the summer heat, which keeps young children indoors for much of the day from June to September.

Neither city is easy without a car, but Los Angeles is a little better. Its Metro rail links downtown with Hollywood, Pasadena, Long Beach and Santa Monica, and Santa Monica, Venice and Old Pasadena are pleasant to walk, even if the freeways between them are often jammed.

Phoenix has a single light rail line, running from the airport through downtown to Tempe, and summer heat makes even short walks hard. In return, its roads and parking are easy, so driving there is much less stressful than in Los Angeles.

For shopping, Los Angeles is far ahead. It has luxury on Rodeo Drive, streetwear and vintage on Melrose, independent boutiques on Abbot Kinney and the Rose Bowl flea market for serious hunting. Phoenix is mostly malls, plus the galleries and Western wear shops of Old Town Scottsdale.

Phoenix does have one thing Los Angeles cannot match: Native American work, including Navajo and Zuni silver and turquoise, Hopi katsina carvings, pottery and rugs. These are best bought from museum shops and reputable galleries.

Phoenix is the cheaper of the two. Chain hotels along the freeways are good value all year and resort rates drop sharply in summer, though the winter high season is costly. Hiking is free, and Sonoran food is a cheap way to eat well.

Los Angeles is expensive on almost every count, from hotels near the coast to the hire car, parking, tips and theme park tickets. Taco trucks, Koreatown kitchens, the free beaches and the free Getty collections lower the bill, but not by much.

In live music and theatre, Los Angeles is in another league. There is the Philharmonic at the Walt Disney Concert Hall and summer picnics at the Hollywood Bowl, along with LA Opera, the rock rooms of the Sunset Strip, Hollywood's comedy and improv and the jazz of Leimert Park. On their own, these are a reason to visit.

Phoenix has a full set of institutions, but they mostly serve locals: the Phoenix Symphony, Arizona Opera, Ballet Arizona and touring Broadway shows at Frank Lloyd Wright's ASU Gammage. Its most distinctive stage is the small concert hall at the Musical Instrument Museum, and summer is quiet.

The two are level here, but they offer very different kinds of rest. Los Angeles has the Korean bathhouses of Koreatown, with hot and cold pools, body scrubs and heated floors open late, plus yoga and luxury spas, though the city around them is anything but calm.

Phoenix is made for the classic resort rest: large spas at the foot of Camelback and in north Scottsdale, treatments using desert ingredients and a week by the pool in dry winter sun. It has no public bathing culture, though, and the best of it comes at resort prices.