Saint-Martin or Vieques?

Both are excellent beach islands, and the difference is how the beaches are run. On Saint-Martin you get comfort and choice. Orient Bay has sunbeds, water sports and beach restaurants. The calm western bays such as Baie Rouge are good for snorkelling straight off the sand, and Pinel is a short boat ride away.

Vieques offers emptiness. Sun Bay and Media Luna near Esperanza are calm and sheltered, and the refuge beaches in the east have reefs close to shore and very few people. There are no lifeguards, cafés or sunbeds, and some beaches are reached only on rough dirt tracks.

Saint-Martin eats far better. Grand Case alone, with its seafront French and creole dining rooms and the lolos' grilled ribs and lobster at shared tables, has more range than all of Vieques. Add the proper bakeries and French cheese in the supermarkets, and a week's eating here is a real pleasure.

On Vieques, eating out is casual and limited: fish tacos and mofongo on Esperanza's seafront, and fried snacks from roadside kiosks. Kitchens keep short hours and often close out of season, so self-caterers should stock up before the crossing.

Neither island is a sightseeing destination, and each takes a morning or an afternoon. Saint-Martin has the view from Fort Louis over Marigot's harbour and a few streets of balconied creole houses. Vieques has the more unusual story. The small museum in the fort above Isabel Segunda covers the decades the island was used as a naval bombing range, and there are lighthouses and an ancient ceiba tree to round out a drive.

Saint-Martin has a real night out if you want one. Grand Case has street music and late terraces on winter evenings, Orient Bay has sunset beach bars, and the clubs and casinos of Simpson Bay and Maho are just over the border.

Vieques goes quiet after dark. There are a few seafront bars in Esperanza, weekend locals' bars in Isabel Segunda and no clubs, and for many visitors the only evening outing is the bioluminescent bay.

Vieques has the outdoor experience you'll remember. On a moonless night in Mosquito Bay, every paddle stroke glows blue-green, and the wildlife refuge at both ends of the island is good for cycling and birding among dry forest, salt ponds and semi-wild horses. The hills are low, though, and there is nothing demanding to hike.

Saint-Martin's outdoors is more active than wild. It has forest trails up Pic Paradis, a zipline park, kitesurfing in Orient Bay's trade winds and reef snorkelling around Tintamarre and Creole Rock.

Here Saint-Martin is far ahead. Anguilla's quiet beaches are a short ferry ride from Marigot, and St Barths' polished Gustavia harbour makes a longer crossing. Saba and Sint Eustatius make a full day, and Philipsburg and the low-flying planes at Maho fill a half-day on the island itself.

Vieques is an island for staying put. The one rewarding outing is a chartered boat to Culebra's Flamenco Beach, and a day in old San Juan is a long one.

Saint-Martin is easier with children. Le Galion's shallow, reef-sheltered bay and the short boat to Pinel suit small swimmers, there are plenty of villas with pools, and the treetop park and the planes at Maho give older children something besides the sea.

Vieques charms families with its roadside horses and the night kayak on the glowing bay. It has nothing else built for children, though, and its beaches have no lifeguards or shade. Medical care is limited, and the ferry adds effort.

You need a car on both islands, but Saint-Martin is less work. You fly straight in, nothing is more than about forty minutes' drive away, and minibuses link Marigot, Grand Case and Philipsburg. The main nuisance is traffic around the lagoon bridges.

Vieques starts with a ferry from Ceiba that is prone to sell-outs and schedule changes, or a small plane. The refuge beaches then need a jeep on dirt roads, and jeeps should be booked well ahead because there are few of them.

Saint-Martin has two kinds of shopping. Marigot has its waterfront market and French boutiques, and Philipsburg's Front Street is a long run of duty-free shops. Its guavaberry liqueur also makes a better souvenir than anything on Vieques. On Vieques, shopping means a few galleries and craft shops in Esperanza and Isabel Segunda, plus groceries.

Both are expensive, but Vieques is a little easier on a budget. Simple guesthouses in Esperanza, self-catering and the ferry instead of a flight keep costs down, and the beaches have nothing to pay for. Jeep hire is the unavoidable cost.

On Saint-Martin you pay French restaurant prices and high winter rates for rooms and villas, plus a hire car and boat trips. The lolos, supermarket picnics and the quieter late-spring and summer months are the ways to spend less.

Neither island has a theatre or concert programme, but Saint-Martin has more music to stumble on. Steel pan, zouk and soca bands play at beach bars and in Grand Case, and Carnival brings parades and soca competitions. On Vieques, live music is the odd guitarist in an Esperanza bar and the yearly patron saint festivities in Isabel Segunda.

Neither island has a spa culture, so the difference is in the kind of rest. Saint-Martin has proper treatments in its larger resort spas and independent studios, and a villa above Anse Marcel is a peaceful retreat. Vieques has no real spa, but it is quieter all round, with little traffic, no high-rise hotels and long empty afternoons with roosters for company.