San Diego or South Lake Tahoe?

San Diego is clearly better for a beach trip. Its ocean sand runs from the broad strand at Coronado through the boardwalk beaches of Mission and Pacific Beach to the cliff-backed coves of North County, with surf for every level and the calm shores of Mission Bay for small children. The Pacific stays cool, though, and is only really comfortable in late summer.

South Lake Tahoe's beaches are on the lake, under the pines at Pope, Baldwin and Zephyr Cove, with remarkably clear water over white sand. At this altitude swimming is limited to a short midsummer window, and for the rest of the year the shore is for walking and the view.

San Diego eats far better, mostly by eating casually. Baja-style fish tacos, the California burrito stuffed with fries, the long run of Asian kitchens on Convoy Street and taprooms all over North Park and Miramar give you something worth seeking out every day.

In South Lake Tahoe meals are fuel between days outside: casino steakhouses and buffets, pizza and brewpubs along Highway 50, and a cabin kitchen that is often the most reliable option. Local craft beer is the one thing the two have in common.

Neither is a great museum city, but San Diego has a solid day or two of sights. There are the museums and Spanish Colonial Revival buildings of Balboa Park, the USS Midway on the waterfront, the adobes of Old Town and Mission San Diego de Alcalá, the first of California's missions.

South Lake Tahoe's list is short: the lakeside estates at the Tallac Historic Site, Vikingsholm at the head of Emerald Bay and a small museum on the Washoe people and logging. That fills a morning, and then you are back outdoors.

San Diego gives you far more choice in the evening. The Gaslamp has rooftop bars and clubs, Pacific Beach has a young beach-bar strip, and North Park and Hillcrest have relaxed cocktail bars and taprooms, with Hillcrest at the centre of the city's gay nightlife. Even so, last call is 2am and it is no party capital.

South Lake Tahoe can actually keep you out later, because the casinos at Stateline stay open all night, but that is the only real option. Otherwise evenings mean après-ski by the gondola and an early night before the slopes or the trail.

San Diego's outdoors are coastal and easy-going. There are trails on the Torrey Pines bluffs, sea lions and kayak routes into the sea caves at La Jolla Cove, surf breaks for every level and grey whales offshore in winter, with pine forest and the Anza-Borrego badlands inland.

South Lake Tahoe is the stronger choice by a distance. The deep blue lake ringed by granite peaks, Emerald Bay, the lake-dotted basins of Desolation Wilderness a few minutes away, the Rim Trail and skiing at Heavenly, Kirkwood and Sierra-at-Tahoe make it a real mountain base in winter and summer alike.

San Diego's outings are more varied, mainly because Mexico is next door. You can reach Tijuana by trolley and a walk across the border, or drive to the Valle de Guadalupe vineyards beyond Ensenada. Closer to home are Temecula wine country, the apple-pie town of Julian, train rides up the coast and Los Angeles about two hours away.

From South Lake Tahoe the drives lead into Gold Rush and silver-boom country: the boardwalks of Virginia City, Genoa, Coloma and the Amador vineyards, with Reno for a bigger casino city. They are pleasant, but best kept for a day of poor weather.

San Diego is one of the easiest family trips anywhere. The zoo in Balboa Park and its Safari Park, SeaWorld, Legoland and the Birch Aquarium give a full day out for every age, and the mild climate means outdoor plans rarely fall through.

South Lake Tahoe suits families who want to be outside: shallow lake beaches and paddleboards in summer, ski schools and sledding hills in winter. With no zoo, aquarium or theme park, a stormy day leaves little to do, and the casino corner is no place to linger with children.

You need a car for most of a trip in either place, though San Diego is a little easier. Its downtown is walkable from the Gaslamp to Little Italy, the trolley runs to Old Town and the border, and coastal trains reach the North County beach towns, but the beaches and big parks are far apart.

In South Lake Tahoe the walkable area is just the corner around Stateline and the gondola, with ski shuttles along the highway in winter. Summer weekends bring slow traffic around Emerald Bay, and winter storms bring chain controls on the roads in.

Neither is a shopping destination, but San Diego offers far more. There are luxury brands at Fashion Valley, a large outlet centre by the border, independent and vintage shops in North Park and Little Italy, galleries in La Jolla and Mexican crafts in Old Town. In South Lake Tahoe shopping means ski gear, rental stores, a supermarket run for the cabin and souvenirs at the gondola base.

Both are expensive, so the difference is in where the money goes and when. In San Diego the costs are beach and downtown hotels that peak in summer, tax and tip on every meal, and steep admission at the zoo and theme parks, though taco shops and free beaches help.

South Lake Tahoe's costs rise and fall with the seasons. Peak ski weeks and high summer are expensive and lift tickets are steep, but casino hotels on the Nevada side cut their rates midweek and in spring and autumn, and a cabin kitchen keeps food bills down.

San Diego is much stronger on stage. The Old Globe in Balboa Park and the La Jolla Playhouse are serious producing theatres that have sent shows to Broadway, the symphony plays a summer season on the bay, and the opera gives a short season downtown.

South Lake Tahoe's live entertainment comes mostly from casino showrooms, with touring rock, country and comedy acts, plus summer evenings outdoors such as Shakespeare on the beach at Sand Harbor and concerts at the Tallac estates. Out of season there is little beyond a bar band.

The two are broadly level here, and neither has a bathing tradition, so the difference is in the kind of rest on offer. San Diego's calm comes from beach-town mornings, sunset walks and the long-standing yoga and meditation culture of Encinitas, with resort spas in La Jolla, Coronado and Carlsbad.

South Lake Tahoe offers mountain quiet and real hot springs instead: the mineral pool at Grover Hot Springs in an alpine meadow and the Carson Valley resorts over the pass, both easy for an afternoon soak after a day outside.