Atlantic City or Washington DC?

This is Atlantic City's whole point. A wide, flat beach of pale sand runs under the Boardwalk the length of Absecon Island and costs nothing to use. It continues into quieter stretches at Ventnor, Margate and Longport, with lifeguards all summer and open Atlantic surf, so you swim between the flags.

Washington is an inland river city, and nobody swims in the Potomac. The nearest sand is on the Chesapeake around Annapolis, small and brackish, and the real ocean beaches are a weekend away. Most visitors cool off in a hotel pool.

Atlantic City eats in two ways. The resorts have polished but standard steakhouses and buffets. Older seaside food carries on outside them: Ducktown's Italian-American kitchens, huge subs, boardwalk pizza, crab shacks on the back bays and saltwater taffy. It fills you up, but it rarely becomes the reason for a trip.

Washington gives you more reasons to plan your meals. There are Ethiopian restaurants around Shaw and U Street, pupusas in Columbia Heights, the local half-smoke, and Chesapeake crabs and oysters in season. Eastern Market and Union Market are good for grazing, and serious tasting menus in Logan Circle and Penn Quarter take care of the top end.

Atlantic City's heritage is the American seaside resort itself. It has the original Boardwalk, the street names from Monopoly, Boardwalk Hall with the world's largest pipe organ, and Lucy the Elephant in Margate. It is charming, but casino towers have replaced most of the old architecture, and a day covers it.

Washington is in another league. The Smithsonian museums, the National Gallery and the African American history museum stand within walking distance of each other, nearly all free. Around them are the Capitol, the Lincoln Memorial, the Library of Congress and Arlington Cemetery, enough for a full week.

Both cities offer a decent night out, but in different settings. In Atlantic City everything happens inside the casino resorts. Their bars and gaming floors never close, and on summer weekends they put on nightclubs and pool parties. Outside them there is no bar street to wander, and midweek or in winter it goes quiet.

Washington's nightlife is on the streets. You'll find cocktail bars and rooftops along 14th Street and U Street, cheap late drinks in Adams Morgan, dive bars on H Street and beer gardens by the river at the Wharf. Dupont Circle is the centre of the LGBTQ+ scene, and the busiest nights run from Thursday to Saturday.

Around Atlantic City the land is flat: dunes, salt marsh and wide back bays. The Forsythe wildlife refuge is good for herons and shorebirds, and the bays suit kayaking and crabbing. It is a pleasant extra, but there is no scenery to travel for.

Washington is far greener. Rock Creek Park and the C&O Canal towpath start right in the city, and Great Falls brings a rocky gorge with whitewater half an hour upriver. The Blue Ridge and Shenandoah are close enough for proper ridge hikes, with cherry blossom in spring and autumn colour on the ridges.

Atlantic City has two strong days out. Philadelphia's Independence Hall is about an hour and a half away, and Cape May's Victorian streets lie an hour south. Closer by are smaller trips to Wildwood, Smithville and Batsto in the Pine Barrens.

Washington has more choice and more history. Old Town Alexandria is a Metro ride away, then come Mount Vernon, Baltimore by train, Annapolis, and the Civil War battlefields at Gettysburg, Antietam and Harpers Ferry. Philadelphia is reachable from here too, though it makes a longer day.

With children, Atlantic City is really about the beach, plus the rides on the Steel Pier and a climb inside Lucy the Elephant. Away from the sand it is a town of casino floors that under-21s cannot enter, and many families stay instead in Ocean City, which has no bars and a boardwalk full of arcades.

Washington is one of the easiest big American cities with children. The dinosaur halls, the rockets at Air and Space and the National Zoo are all free and built to teach, and the Mall gives children room to run. The only drawback is the long, hot walks in summer.

In Atlantic City the Boardwalk is a simple straight line to walk, and jitney buses run along Pacific Avenue day and night. The streets inland from it are not pleasant on foot, especially after dark. The wildlife refuge, Cape May and the neighbouring shore towns really need a car.

Washington's flat grid and clean, colour-coded Metro reach almost everything, including Arlington, Alexandria and the airport. Bike-share docks are everywhere for linking the monuments. Distances are longer than they look and Georgetown has no Metro station, but you only need a car for the countryside.

Atlantic City is somewhere to stock up rather than to browse. Familiar American brands sell at discount in an open-air outlet district a short walk from the Boardwalk, the resorts keep their own indoor rows of clothes and gift shops, and the Boardwalk stalls sell swimwear, beach towels and printed T-shirts. Boxes of taffy and fudge are the only souvenirs that really belong to the place.

Washington is where you might spend an afternoon just looking, though it rarely shapes a trip. Instead of outlets you get Georgetown, where boutiques and antique dealers mix with the chains along brick-fronted M Street and Wisconsin Avenue, and a compact block of luxury labels downtown at CityCenterDC. Instead of boardwalk souvenirs there are the weekend craft and second-hand stalls at Eastern Market, and the museum shops on the Mall for a good book or a print to take home.

Atlantic City is the easier city on a budget, provided you pick your dates. Midweek and outside summer, casino hotels discount their rooms heavily, and subs and boardwalk food are cheap. Summer weekends cost much more, and resort fees and parking add up.

In Washington rooms are expensive all year, and restaurants and cocktails are priced for expense accounts. What saves money is that the museums, the zoo and the memorials are free, and staying out in Arlington can bring the room bill down.

Atlantic City's entertainment is built around headliners. Touring pop acts, comedians and boxing fill the casino arenas and Boardwalk Hall, and summer adds free concerts on the beach. There is no orchestra, theatre district or small jazz scene.

Washington has a real stage culture. Arena Stage, the Shakespeare Theatre Company, Woolly Mammoth and Ford's Theatre put on plays, and the National Symphony and the Washington National Opera give it a classical season. U Street's restored theatres, the local go-go music and summer lawn concerts at Wolf Trap add to the mix.

Neither city is built for rest, but each offers a different kind of calm. In Atlantic City the casino hotels have sizeable spas with saunas and indoor pools, and the most peaceful moments are winter mornings on an empty Boardwalk by the grey sea.

Washington's calm is found outdoors more than in treatment rooms. Try an early walk round the Tidal Basin, the gardens at Dumbarton Oaks, or the National Arboretum. The hotel spas and yoga studios are there, but you have to plan the rest yourself.