St John or Saint-Martin?

Both islands are built around their beaches, and St John has the slight edge. What differs is the setting. On St John, the north shore bays from Hawksnest to Francis lie inside the national park with nothing built behind them. Trunk Bay has its marked snorkel trail and turtles graze the seagrass at Maho. You bring your own gear and water, because there is little else there.

Saint-Martin's beaches are more set up for visitors. Orient Bay has sunbeds, water sports and a clothing-optional stretch, while Baie Rouge and Baie Longue on the west coast are quieter places to snorkel straight off the sand. Seaweed can drift onto the Atlantic-facing bays in some months, a problem St John's sheltered north shore rarely has.

Saint-Martin eats far better. Grand Case alone, with its seafront French and creole restaurants and the smoky lolo barbecue stalls beside them, beats anything on St John. Add proper bakeries and supermarkets stocked with French wine and cheese, and even a picnic on the beach is a pleasure.

St John's eating is concentrated in Cruz Bay: grilled fish, beach-bar burgers, painkillers and a few West Indian kitchens for saltfish and stewed goat. With almost everything shipped in, fresh local produce is rare and there is little fine dining, which is why so many villa guests end up cooking for themselves.

Neither island is a sightseeing destination, but St John has more history you can walk through. The Annaberg sugar mill looks out over the sea, the Reef Bay Trail passes estate ruins on its way to Taíno petroglyphs, and Coral Bay keeps the fort where the 1733 slave revolt began. Together they fill a morning or two.

Saint-Martin has the one thing St John lacks, a small museum covering its Arawak, colonial and salt-pan history. Beyond that there are the views from Fort Louis and a few painted creole streets in Marigot, and most visitors see it all in a single morning.

Saint-Martin gives you a real choice of evenings. Grand Case has street music on busy winter nights and terraces that stay open late, and Orient Bay's beach bars fill up at sunset. A short drive across the open border, Simpson Bay and Maho have clubs and casinos that run well past midnight.

St John's evenings consist of rum drinks at the open-air bars on the Cruz Bay waterfront and a couple of spots in Coral Bay. It is sociable but brief, and anyone wanting a late night has to take the ferry to St Thomas.

St John is in another league here. Because most of the island is national park, steep dry forest runs down to empty headlands and reefs. The snorkelling around Waterlemon Cay and Maho Bay brings turtles, rays and coral within easy reach, and the trails to Ram Head and around Lameshur cross country with almost nothing built on it.

Saint-Martin has a greener, hillier interior than people expect, with forest paths up Pic Paradis and a protected marine reserve around Tintamarre and Creole Rock. Its distinct strength is wind. The steady trade winds at Orient Bay make it a kitesurfing and windsurfing spot, which St John's calm bays are not.

Saint-Martin has the wider choice, and more of it is easy. Anguilla's long, quiet beaches are a short ferry ride from Marigot, and polished Gustavia on St Barths is a longer crossing. Philipsburg's boardwalk and Maho Beach are reachable by road. Saba and Sint Eustatius are there for a longer day.

From St John, St Thomas and the old Danish streets of Charlotte Amalie are a short ferry ride away. The British Virgin Islands are close too, Jost Van Dyke and The Baths on Virgin Gorda among them, but going there means a passport, customs and limited ferries, so most people go by charter boat.

Saint-Martin is the easier island with children. Reef-sheltered Le Galion and the short boat ride to Pinel give toddlers calm water, villas with pools are common, and there is a treetop park, glass-bottom boats and the low-flying planes at Maho for days off the beach.

St John has wonderful gentle sea, with turtles at Maho Bay in water a child can stand in, but very little else. The flight, taxi and ferry make for a long arrival, there are few lifeguards, and the villas sit up steep, winding hills, so it suits families who are happy to spend every day in the water.

Getting around is about equally awkward on both, for different reasons. St John has no airport, so you fly to St Thomas, take a taxi to Red Hook and catch a ferry. On the island you drive a hired jeep on the left along steep switchbacks, although open-air safari taxis do cover the north shore beaches.

Saint-Martin's runway sits beside Maho Beach, so you land on the island itself, but you will still want a car. The minibuses only link the towns, and traffic backs up around Marigot and the lagoon bridges. The open border costs nothing to cross, and water taxis go out to Pinel and Tintamarre.

Saint-Martin offers two quite different kinds of shopping. Marigot's waterfront market sells spices, rum and fabrics, with French boutiques and perfume shops behind it. Across the border, Philipsburg's Front Street is lined with duty-free jewellery and electronics shops. Guavaberry liqueur is the souvenir worth taking home.

On St John, the shopping fills an hour in the small courtyards near the Cruz Bay ferry dock, among galleries, hook bracelets and hand-painted pottery. Anyone after duty-free has to cross to Charlotte Amalie.

Both islands cost a lot in winter, and St John is the harder on a budget. Nearly everything there is shipped in, so meals and groceries are steep, and the jeep, taxis and ferries add up. What helps is that the park beaches and trails are mostly free, and the Cinnamon Bay campground is a cheaper way to stay.

Saint-Martin is expensive too, with French prices in its restaurants and charges for car hire and boat trips. Lolo barbecues and supermarket picnics keep daily costs down more easily, though, and on both islands rates fall once the winter season is over.

Neither island has a theatre or concert hall, so live music means bands at bars. On St John that is guitarists and the occasional steel pan or reggae band in Cruz Bay, and the big event is the St John Festival in early summer, with quelbe music, the islands' traditional folk style.

Saint-Martin's bands lean towards zouk and soca, mostly at Grand Case and at hotels, and its Carnival adds costumed parades and calypso competitions.

St John is the quieter place to switch off. With most of the land protected, there is hardly any traffic and no high-rise building, and the nights are quiet apart from the tree frogs. Massage therapists come out to villas, and the days run on early swims and early evenings.

Saint-Martin has more resort spas and beachside yoga, and a villa above Anse Marcel or on the west coast can be just as peaceful. The traffic and cruise-day crowds around Marigot make it harder to forget the rest of the world, and neither island has a real spa tradition to plan a trip around.