Marco Island or St. Petersburg, Florida?

On the beach the two are evenly matched, and the difference is in how you reach the sand. Marco Island's crescent of pale, shell-strewn sand runs right along the island's western shore, so many visitors stay steps from it, with the Tigertail lagoon and sandbar for wading and the undeveloped Keewaydin Island a short boat ride away.

St. Petersburg's beaches lie on the barrier islands west of the city, so staying downtown means a short drive or bus ride. In return you get more variety: Pass-a-Grille's old village, the wilder park shore at Fort De Soto, and Clearwater and Caladesi Island to the north. The winter sea is also a few degrees cooler here.

Both cook Gulf seafood first, grouper sandwiches and stone crab claws included, but St. Petersburg has far more range behind it. Central Avenue and the Grand Central and Edge districts add modern American kitchens, brunch places and a few ambitious chef-led restaurants, the craft brewery scene is genuinely strong, and the Cuban and Spanish cooking of Ybor City is across the bay.

Marco Island keeps to waterfront grills, resort dining rooms and the dockside fish platters of Goodland, with a few steakhouses and Italian places beyond that. For a more polished dinner you drive to Naples.

St. Petersburg is the place for sightseeing. The Dalí Museum's concrete and glass building anchors a cluster of museums on the downtown waterfront, from fine art and Western art to Chihuly glass and the Arts and Crafts Movement, with 1920s Mediterranean Revival buildings and street murals beyond.

Marco Island is a resort community built from the 1960s, and its one real cultural stop is the historical museum, with its story of the Calusa people and the carved wooden figures found on the island. Anything more means a trip to Naples.

Neither is a clubbing town, but St. Petersburg has a proper evening out. Cocktail bars, rooftop terraces, sports bars and taprooms sit within walking distance of each other along Central Avenue, beach tiki bars start the night at sunset, and Ybor City in Tampa is there for something rowdier.

On Marco Island, the evening is a sunset drink and dinner, then quiet. A few resort lounges and marina bars stay open for a mellow, older crowd, and Goodland's dockside bars are at their liveliest on winter weekend afternoons rather than at night.

Both are flat, watery and full of mangroves, but Marco Island sits closer to real wilderness. It is the northern gateway to the Ten Thousand Islands, with Rookery Bay alongside, manatees in the canals, some of Florida's best fishing for snook and tarpon, and Everglades National Park, Big Cypress and the Fakahatchee Strand within an hour for alligators and cypress boardwalks.

St. Petersburg's nature is gentler and more suburban: paddling trails at Weedon Island and Shell Key, birding at Fort De Soto, and the paved Pinellas Trail for long bike rides.

St. Petersburg has the more varied set of outings. Tampa's Ybor City and the minarets of the old Tampa Bay Hotel are across the bay, the Ringling's mansion and circus museum in Sarasota and the Greek sponge docks of Tarpon Springs are each under an hour, and Orlando is within reach for a long day.

From Marco Island the best excursions are into the Everglades. For towns there is Naples, Everglades City and Chokoloskee, and the Edison and Ford Winter Estates in Fort Myers, a pleasant but shorter list.

Both have calm, shallow water that suits small children, but St. Petersburg has much more to do off the beach. Great Explorations is in the city, the Clearwater Marine Aquarium is to the north, and Tampa adds Busch Gardens, ZooTampa and the Florida Aquarium, with Orlando close enough for a split stay.

Marco Island is simpler and quieter: shelling, wading at Tigertail, dolphin boat trips and resort pools with children's programmes. For a zoo or museum you go to Naples, and an Everglades airboat ride is the big outing for older children.

You will want a car in both, but St. Petersburg asks a little less of it. Downtown is compact enough to walk between the pier, museums and Central Avenue, a trolley loop covers the core, and a rapid bus runs out to St. Pete Beach.

Marco Island has pleasant cycle paths on its small, flat streets and little else beyond a limited county bus to Naples. Reaching the Everglades, Naples or the airport, three quarters of an hour away, assumes you are driving.

Neither is a shopping destination, and St. Petersburg is only slightly ahead. Its strength is independent: vintage and record shops on Central Avenue, local glass and prints, and the Saturday Morning Market in winter, with brand-name malls in Tampa.

Marco Island has small plazas of resort wear and shell souvenirs, but upmarket boutiques and galleries are close by on Fifth Avenue South and Third Street South in Naples.

Marco Island is the costlier stay of the two. Its beachfront resorts and condos are priced for a well-off winter crowd, eating out is expensive across the board, and you cannot do without a car. Weekly condo rentals with kitchens do help families and groups.

St. Petersburg leaves more room to save. You can stay downtown or a little inland instead of on the sand, take the bus out to the beach, and spend your days in free parks and along the waterfront. In both places summer brings lower rates, along with the heat and storms.

St. Petersburg has a modest but dependable programme. The Mahaffey Theater hosts the Florida Orchestra and touring shows, with a regional theatre company, a former church used as a concert hall and an open-air courtyard for bands, and Tampa's large arts centre handles opera and ballet.

Marco Island has a small community theatre and musicians in resort bars over the winter. A real concert means the drive to Naples for its philharmonic, and in summer there is little on.

Neither has a bathing tradition, so relaxation in both means resort spas, yoga and the pace of the place. Marco Island does slow living a little better, because the whole island is quiet and the large beachfront resorts put their spas and pools right on the Gulf.

St. Petersburg is calm in pockets, the sleepy streets of Pass-a-Grille and the shaded waterfront parks downtown, but it is a working city around them, and its spas cluster at the large historic beach hotels.