Atlantic City or Portland, Maine?

Here the gap is wide, and it comes down to the water. Atlantic City sits right on its beach: broad, pale, free sand under the Boardwalk, lifeguards all summer, and an Atlantic warm enough by August for proper swims between the flags. Ventnor and Margate carry the beach on south in quieter stretches.

Portland's best sand is out of town, at Crescent Beach, Higgins Beach or the old resort strand of Old Orchard. The Gulf of Maine stays chilly even at the height of summer, so you walk, sunbathe and paddle there rather than swim for long.

Portland is the place to eat. Lobster rolls at harbour shacks, oysters from Maine estuaries, chef-run restaurants and a cluster of craft breweries in East Bayside let you plan a whole trip around meals.

Atlantic City feeds you well enough but rarely surprises. Inside the casinos you get polished steakhouses and buffets. Outside them are the Italian-American kitchens of Ducktown, oversized subs, boardwalk pizza and crab shacks on the back bays. The saltwater taffy is more memorable than most of the dinners.

Neither city makes a museum trip, but Portland gives you more to look at. It has the brick and granite Old Port rebuilt after the 1866 fire, the Portland Museum of Art with its Winslow Homers, Victoria Mansion and Portland Head Light.

Atlantic City's interest is in having set the pattern for the American seaside resort. The original Boardwalk, the Monopoly street names, the giant organ in Art Deco Boardwalk Hall and Lucy the Elephant fill a day among the casino towers.

Atlantic City stays up much later. The casinos never close, so a bar or gaming floor is always open in the small hours, and summer weekends bring resort nightclubs and pool parties. The catch is that the streets between the resorts are bleak after dark, and midweek winter nights fall flat.

Portland is a town of bars and taprooms: oyster and cocktail bars in the Old Port, quieter wine bars on Munjoy Hill, last orders at 1am and no real clubs. It is better for a good drink after dinner than for a long night.

Portland has the better outdoors, and most of it is on the water. Ferries run to Peaks and Chebeague for island walks and cycling, sea kayaks and schooners head out into Casco Bay, and there are clifftop rambles at Two Lights. The White Mountains are about two hours off for real hiking.

Atlantic City's landscape is flat marsh and back bay. The Forsythe refuge is excellent for herons and shorebirds, and the Pine Barrens suit a quiet paddle, but these are extras to a beach stay rather than a reason to go.

Both make good bases, but the outings differ in kind. From Atlantic City the big prize is a major city: Philadelphia, with Independence Hall and its museums, is about an hour and a half away. Victorian Cape May and the boardwalk towns of Ocean City and Wildwood are closer.

From Portland the outings are a string of small coast towns. Kennebunkport, Ogunquit and colonial Portsmouth lie to the south, and Bath, Boothbay Harbor and Camden to the north. Expect pretty harbours and maritime heritage rather than big-city sights.

Portland is the easier family base. It is small and calm, the Children's Museum and Theatre of Maine suits younger children, and ferry rides, tide pools and lighthouse forts fill the days, even without a zoo or a big aquarium.

Atlantic City has the bigger beach and the rides on the Steel Pier, but the city is built around casinos that children cannot enter, and there are rundown blocks off the Boardwalk. Many families stay in Ocean City instead and visit for the day.

Neither is easy beyond its centre, and for the wider area both push you towards hiring a car. What differs is the shape. Atlantic City is a long line: the Boardwalk, plus jitneys running round the clock on Pacific Avenue, with unappealing streets inland.

Portland's peninsula is a compact cluster of walkable neighbourhoods, the Old Port, the West End and Munjoy Hill, steep in places. Island ferries leave from the waterfront, and a train runs to Boston.

Portland is the better place to browse. Independent boutiques on Exchange and Fore Streets sell pottery, woollens and Maine-made homewares, there are galleries on Congress Street, and the outlet town of Freeport, twenty minutes north, is good for outdoor gear. In Atlantic City you mostly get chain outlets, casino arcades and Boardwalk T-shirts, and saltwater taffy is the one thing worth carrying home.

Atlantic City is easier on the wallet, as long as you choose your dates. Casino hotels cut midweek and off-season rates hard to fill their rooms, and the beach, the Boardwalk and much of the entertainment are free. Summer weekends and resort fees narrow the gap.

Portland is costly for much of the year. Room rates match big cities in summer and on foliage weekends, and meals built around seafood add up. Shacks, food trucks and an off-season visit help, but it rarely feels cheap.

There is about as much to see in each, but of a different sort. Atlantic City is about big names: touring rock and pop acts, comedians and boxing in casino arenas and Boardwalk Hall, plus free beach concerts in summer.

Portland has a small but settled cultural life of its own, with the Portland Symphony Orchestra at Merrill Auditorium, professional theatre at Portland Stage, and bands and folk acts at the historic State Theatre.

Atlantic City offers a massage and an indoor pool in a casino-hotel spa, while Portland offers a ferry ride to a quiet island in Casco Bay. The resort spas have the treatments and saunas, but the gaming floors around them never really go quiet. The most peaceful hour in Atlantic City is an early walk on the empty Boardwalk in winter.

Portland has hotel and day spas too, but its real way of helping you unwind is its slow pace: dusk on the Eastern Promenade, a long lunch by the water, or a cold summer dip followed by a waterfront sauna.