Flagstaff or San Diego?

There is no contest here. Flagstaff is a mountain town far from any coast. Swimming there means Slide Rock and the cold, crowded creek pools of Oak Creek Canyon, or a hotel pool.

San Diego has a long coastline of sandy beaches, from the wide strand at Coronado to the boardwalk at Mission and Pacific Beach and the gentle surf at La Jolla Shores, with quieter cliff-backed beaches further north. The Pacific stays cool, so swimming is mostly a late-summer pleasure, but the beach is part of every day here.

Both pour excellent craft beer. Flagstaff's brewery taprooms cluster downtown and in the Southside, and San Diego's across North Park, Miramar and the coast. Beyond the beer, Flagstaff offers a modest university-town range with touches of Navajo frybread and green chile.

San Diego eats far more widely. The border gives it Baja fish tacos and late-night taco shops, and it adds fresh seafood, the Asian kitchens along Convoy Street and Little Italy's restaurants. Neither is a fine-dining destination, but San Diego gives you much more to look forward to at mealtimes.

Flagstaff's sights are few but distinctive. The Lowell Observatory, where Pluto was discovered, and the Hopi, Navajo and Zuni collections at the Museum of Northern Arizona lead the list, with a railroad-era downtown on Route 66 alongside. A day or two covers them.

San Diego has more to fill the days. Balboa Park gathers a run of museums in its exposition buildings, and the USS Midway, Old Town's adobes, the first California mission and Cabrillo National Monument add history around the bay. Neither city is a major museum destination, but San Diego offers several days' worth.

Flagstaff's evenings are a stroll between brewery taprooms, cocktail bars and old Route 66 saloons downtown and in the Southside. They are livelier in term time and mostly over well before the small hours.

San Diego has more range and later nights. The Gaslamp Quarter has rooftop bars and dance clubs, Pacific Beach has a rowdy student bar strip, and Hillcrest and North Park suit cocktails and the city's gay scene. Even so, it is a city for a good drink rather than a big night out.

This is where Flagstaff pulls ahead. It sits under the volcanic San Francisco Peaks in a huge ponderosa pine forest, with trails from town and skiing in winter. The lava fields of Sunset Crater are close by, the Grand Canyon and Sedona's red rock are an easy drive away, and the dark skies add stargazing.

San Diego's outdoors are gentler and different in kind. It has sea lions at La Jolla Cove, sea caves to kayak, tide pools at Cabrillo, surf all along the coast and whales passing in winter, with mountains and the Anza-Borrego desert an hour or more inland. It is excellent for an active beach vacation, but the landscapes are less grand.

Both have plenty within a drive, and in both you need a car. Flagstaff's outings lean towards ancient and frontier history: the Sinagua ruins at Walnut Canyon and Wupatki, the Verde Valley cliff dwellings, hillside Jerome, the railway to the Grand Canyon and the Hopi mesas.

San Diego's list is shaped by the border. Tijuana is a trolley ride away and the Valle de Guadalupe vineyards lie further south, alongside Temecula's wineries, apple-pie Julian, the beach towns up the coast by train and Los Angeles. Choose Flagstaff for heritage and landscape, San Diego for wine, Mexico and the coast.

Flagstaff is a relaxed place to bring children. It has telescope evenings at the observatory, dinosaurs at the museum, rope courses in the pines and snow play in winter. The altitude, cold nights and long drives between outings are the drawbacks.

San Diego is in another league for families. The zoo, the Safari Park, SeaWorld and Legoland could each fill a day, Mission Bay's calm water suits small paddlers, and the mild weather means plans rarely change. The only real effort is the distance between the big parks.

Neither is easy without a car. Flagstaff's downtown and Southside are walkable and its urban trails make cycling practical. But the mountain, the monuments, Sedona and the Grand Canyon lie beyond any bus, and winter snow can make the mountain roads hard going.

San Diego does a little better. The trolley links downtown, Old Town and the border, and coastal trains reach the North County beach towns. La Jolla, the beaches and the big family parks still sit far apart, so most visitors hire a car anyway.

Flagstaff is worth browsing for one thing: Native American craft. Look for Navajo rugs, Hopi kachina carvings, and silver and turquoise jewellery, best bought from established dealers or from the artists themselves. Otherwise it is outdoor gear and Route 66 souvenirs.

San Diego has more variety. There are the luxury brands of Fashion Valley, an outlet centre at the border, boutiques and vintage shops in Little Italy and North Park, and galleries in La Jolla. Neither is a shopping destination, but San Diego offers more ways to spend an afternoon.

Flagstaff is the cheaper of the two. Chain motels along old Route 66 keep a basic stay modest and brewery meals are reasonable, though summer weekends push room rates up, and a hire car, fuel and park fees add up.

San Diego costs noticeably more. Hotels near the beaches and downtown are expensive, and the zoo, SeaWorld and Legoland charge high admission. Taco shops, free beaches and Balboa Park's gardens help, but in both places tips are added to every bill.

Flagstaff's calendar is modest: the symphony and university concerts, touring bands at the restored Orpheum Theater, community theatre and summer concerts in the pines.

San Diego offers much more, above all in theatre. The Old Globe in Balboa Park and the La Jolla Playhouse are serious producing companies whose shows have gone on to Broadway, and the symphony plays a summer season on the bay. An evening there is worth booking, though neither city is a reason to travel for the stage alone.

Neither city has a bathing tradition. Flagstaff's calm comes from its setting, with cool pine-scented evenings and bright stars, but it has few spas, and anyone wanting treatments drives down to Sedona. The altitude can also disturb sleep at first.

San Diego makes slowing down easier. It has resort spas in La Jolla, Coronado and Carlsbad, the yoga and meditation culture of Encinitas and unhurried beach mornings, as long as you stay away from downtown and Pacific Beach.