San Diego or Sonoma?

San Diego is a beach city and Sonoma is not. San Diego has around 110km of shoreline, from the broad sand at Coronado to the boardwalk of Mission and Pacific Beach and the gentle breakers of La Jolla Shores. The water is only properly pleasant in late summer, but the choice of beaches is enormous.

In Sonoma the sea is more than an hour away, at Bodega Bay. That coast is beautiful to look at but cold and dangerous to swim. A swim there means a hotel pool or the gravel banks of the Russian River in summer.

The two eat equally well but in completely different ways. San Diego is casual and varied: Baja fish tacos, late taco shops, a run of Asian kitchens on Convoy Street and craft breweries in North Park and along the coast. Beer is what you drink there.

Sonoma is about wine and the long table. Tasting rooms circle the plaza, and the cooking is seasonal Californian, built around local cheese, olive oil and oysters. The choice of restaurants is small and there is little to eat late, but a slow lunch with a bottle from the valley is the whole point.

San Diego has noticeably more to see. Balboa Park alone holds a day of museums, from art to air and space, inside its Spanish Colonial Revival buildings. The USS Midway, the historic ships of the Maritime Museum and the adobes of Old Town add more.

Sonoma's history is compact and genuine: the plaza where the Bear Flag Revolt began, the barracks and General Vallejo's house. Between them the two cities book-end California's mission chain, with the first mission in San Diego and the last on Sonoma's plaza. Sonoma's sights fill half a day, San Diego's two or three.

After dark San Diego is in another league. The Gaslamp Quarter has rooftop bars and dance clubs, Pacific Beach is a rowdy strip of student and surfer bars, and Hillcrest and North Park have cocktail bars, taprooms and the city's gay scene.

Sonoma's evenings end with dinner. A wine bar or a saloon on the plaza may keep you out a little longer, but the town is quiet by late evening and has no clubs at all.

Both are good bases for time outdoors, but San Diego offers more variety. In one stay you can watch sea lions at La Jolla Cove, walk the bluffs of Torrey Pines, surf, look for grey whales in winter, hike the pine forests of the Cuyamaca Mountains and drive out to the Anza-Borrego desert.

Sonoma's outdoors is gentler and closer to hand. Trails start near the plaza, there are redwood groves and views from Bald Mountain at Sugarloaf Ridge, back roads through the vines are made for cycling, and balloons rise over the valley at dawn. It is lovely in spring, but the summer heat on the valley floor limits it.

Sonoma has the stronger day trips, chiefly because San Francisco is an hour's drive away. Napa, Healdsburg, Petaluma's Victorian riverfront and Sausalito on the bay are all close too, although apart from the city most outings are another wine valley.

San Diego's options are more mixed. They include Tijuana by trolley and on foot, the Valle de Guadalupe vineyards in Mexico, Temecula's wineries, Julian in the hills and the beach towns up the coast by train. Los Angeles is about two hours away. Both cities need a car for most outings.

San Diego is one of the easiest family destinations anywhere. The zoo in Balboa Park, the Safari Park, SeaWorld and Legoland could each fill a day, and the mild weather means outdoor plans rarely fall through. Restaurants and hotels are relaxed about children.

Sonoma is safe and calm but built for wine tasting. The plaza playground, the miniature railway and a wildlife park near Santa Rosa will entertain children for a day or two. Families are generally better off staying in San Francisco and visiting Sonoma for an afternoon.

Both need wheels, but San Diego gives you more without them. Downtown, Little Italy and the waterfront are walkable, the trolley runs to Old Town and the border, and coastal trains reach the beach towns. You will still want a car or ride-hailing for La Jolla and the big parks.

In Sonoma only the plaza and the few blocks of tasting rooms around it are walkable, and the buses are of little use. For winery days you need a driver or a tour, so that nobody has to drive after tasting. Cycling works for the wineries near town.

Neither city is a shopping destination, but San Diego has more range. Fashion Valley has department stores and luxury brands, there is a big outlet centre by the border, North Park and Little Italy have vintage and design shops, and La Jolla has galleries.

Sonoma's shopping is a stroll round the plaza arcades for kitchenware, art, cheese and olive oil. Above all you buy wine straight from the people who made it, which San Diego cannot match.

Both are expensive, but San Diego is the easier of the two to keep in check. Its theme parks and beach hotels are costly, but taco shops, brewery taprooms, free beaches and the Balboa Park gardens give you cheap days.

Sonoma has few such escapes. Rooms are scarce and priced for wine weekends, tasting fees add up, and you have to pay for a car or a driver. Budget travellers usually stay in Santa Rosa or Petaluma and picnic among the vines.

San Diego has a serious theatre scene. The Old Globe in Balboa Park and the La Jolla Playhouse both produce their own shows, some of which have gone on to Broadway, and the symphony plays a summer season on an open-air stage by the bay. There is opera downtown too.

Sonoma's programme is mostly summer and outdoors: concerts at Jack London's ruins and on winery lawns. For a proper concert hall you drive half an hour to the Green Music Center. Outside summer there is little on.

Sonoma is the better place to unwind. Boyes Hot Springs has natural mineral water that has drawn bathers for over a century, and Calistoga's mud baths are an hour away. The quiet plaza and early evenings set a slow pace, although nearly all bathing is at resort prices.

San Diego has no bathing tradition. It does have plenty of resort spas in La Jolla, Coronado and Carlsbad, plus a long-standing yoga culture in Encinitas. Calm beach-town mornings help, but downtown and Pacific Beach are far from quiet.