Las Vegas or San Francisco?

Las Vegas has no coast at all. The only warm swimming is in the resort wave pools or at Lake Mead's gravel shore, in a desert basin with no shade. That makes for a hot afternoon, not a beach day.

San Francisco is not a beach destination either, but it has a shoreline worth visiting. Ocean Beach is good for long walks and sunsets, and Baker Beach looks straight at the Golden Gate Bridge. The water is cold and Ocean Beach is unsafe to enter, so the coast is for scenery rather than swimming.

Las Vegas eats on a grand scale, with celebrity-chef outposts, steakhouses and buffets along the Strip. Its best everyday cooking is the long run of Asian restaurants on Spring Mountain Road. Almost all of it is imported, though, and there are no markets and no food of the city's own.

San Francisco builds its cooking on what is around it: bay seafood, Northern California produce and Napa wines. The Mission burrito, sourdough and Dungeness crab are real local dishes, and the Ferry Building market is a good morning out. Its Asian, Italian and Mexican neighbourhoods sit alongside some of the best fine dining in the country.

The sights in Las Vegas are spectacle: the replica skylines and canals of the Strip resorts, the fountain show and the Fremont Street light canopy. The Neon Museum and the Mob Museum tell the city's story well, but after those two a sightseer has little left to do.

San Francisco has much more. Alcatraz, the Golden Gate Bridge, the cable cars on Nob Hill and the painted Victorian houses around Alamo Square sit alongside strong collections at SFMOMA, the de Young and the Legion of Honor. Together they fill three or four full days.

Las Vegas is the stronger night out by a wide margin. Casino bars never close, the resort clubs book star DJs with pool parties before them during the day, and at weekends the Strip stays full until dawn. Queues, dress codes and table service come with it.

San Francisco's nights are smaller and spread across several neighbourhoods: cocktail and mezcal bars in the Mission, old saloons in North Beach, the Castro's gay bars and warehouse clubs in SoMa. Bars stop serving at 2am and weeknights are quiet, so it suits a good evening rather than an all-nighter.

The desert around Las Vegas is superb. Red Rock Canyon has sandstone climbing, Valley of Fire has petroglyphs and Mount Charleston has pine forest. Every outing needs a car, though, and from June to September the heat rules out hiking except at dawn.

San Francisco's outdoors comes with less effort and lasts all year. Golden Gate Park, the Presidio and the Lands End cliff trail are inside the city. The Marin Headlands are half an hour away across the bridge, with Muir Woods' redwoods and Mount Tamalpais beyond. Cycling over the bridge and kayaking on the bay add more.

From Las Vegas, the one classic day out is Hoover Dam together with Boulder City, and it fills about half a day. The Grand Canyon and Zion tours sold on the Strip are long trips to see landscapes, and the towns along the way give you little reason to stop.

San Francisco has good day trips all around it. Napa and Sonoma wine country is about an hour north, ferries cross to Sausalito and Tiburon, Berkeley is a short train ride away, and the coast runs south to Santa Cruz, Monterey and Carmel. A week's stay could have a different day out every day.

Las Vegas does have rides: an indoor amusement park, thrill rides at the top of the tower, a shark aquarium and the Discovery Children's Museum. But casino floors, adult advertising and summer heat make it a stop on a national parks road trip rather than a base for a family vacation.

San Francisco is much easier with children. The Exploratorium and the California Academy of Sciences, with its aquarium and planetarium, can each fill a day. The zoo, the sea lions at Fisherman's Wharf and the carousel and paddle boats in Golden Gate Park cover the rest. The drawbacks are the steep hills and the lack of any big theme park.

Las Vegas looks walkable on a map but is not. The distances between resorts are bigger than they look, walkers are sent through casinos and over footbridges, and the summer heat makes long walks punishing. Most visitors use taxis, ride-hailing and the monorail, and anything out in the desert needs a car.

San Francisco is compact and easy without a car. BART, Muni buses, streetcars, cable cars and ferries all take the same Clipper card. Neighbourhoods such as North Beach, Chinatown and the Mission are good to explore on foot, as long as you can manage the hills.

Las Vegas is better for brand shopping. The Roman-themed arcade at Caesars Palace, the Venetian's canal-side shops and the Fashion Show mall hold most of the big fashion houses under one roof, open late, and two outlet centres cover the bargains. Almost nothing on sale is local.

San Francisco has fewer big brands but more character. Union Square has the flagship stores, Hayes Valley has design boutiques, Valencia Street and Haight-Ashbury have vintage, and Chinatown sells tea and ceramics. It is a city for browsing rather than a shopping trip in itself.

Neither city is cheap, but Las Vegas gives you more ways to save. Midweek rooms on the Strip and downtown can cost little for their comfort, and the suburbs have good, modestly priced places to eat. Weekends, resort fees and the price of drinks and shows on the Strip push costs back up.

San Francisco is expensive from the first night. Hotels are costly across the centre, and tax, service charges and tips are added to every meal. What makes up for it is free: the parks, the walk across the bridge and the coastal trails.

Both cities are good for a night at a show, but very different kinds of show. Las Vegas offers spectacle: water-based acrobatics, aerial shows and magicians in purpose-built theatres, and residencies by stars who rarely tour.

San Francisco has the major arts institutions. Opera and ballet play at the War Memorial Opera House, the Symphony at Davies Symphony Hall, and serious drama at the American Conservatory Theater. Jazz has a dedicated home at SFJAZZ, and the Fillmore carries rock history. The choice comes down to whether you want one big show or a programme of concerts and plays.

Neither city is made for unwinding, and they offer different kinds of rest. Las Vegas has huge resort spas with thermal circuits, saunas and salt rooms, open to non-guests for a day fee. They are best on a weekday morning at a non-gaming hotel, away from the casino noise.

In San Francisco the calm comes in smaller doses: the Japantown bathhouse and the Japanese Tea Garden in Golden Gate Park. Calistoga's mud baths and mineral pools are about two hours north.