Bonaire or Cozumel?

Neither island is a place of long sandy strands, but Cozumel gives the swimmer more comfort. South of San Miguel towards Palancar and Punta Sur, sandy stretches are set up as beach clubs with loungers, ladders into calm water and reef a few strokes out, so a day by the sea is easy to arrange.

Bonaire's west coast water is just as clear and warm, yet most entries are coral rubble or limestone ledges where water shoes help. Its real sand is at Sorobon on Lac Bay, on Klein Bonaire by water taxi, and at Pink Beach in the south. Both islands keep their windward east coasts for looking at rather than swimming.

Bonaire cooks Antillean and Cozumel cooks Yucatecan, and on both islands the best of it is found away from the harbour restaurants. On Bonaire that means goat stew, funchi and the island's iguana soup at roadside snack stands, while Kralendijk's waterfront serves grilled wahoo and Dutch-influenced menus to divers, and with most produce imported many visitors self-cater.

On Cozumel it means cochinita pibil and panuchos a few streets back in San Miguel, evening taco stands around the main square and whole fried fish from the morning's catch. The seafront strip, with its margaritas and Tex-Mex for cruise passengers, is the part to skip, and on neither island is the food a reason to go.

Each island has about half a day of sights, with very different stories behind them. Bonaire's most affecting is in the south, where the obelisks and tiny stone slave huts beside the salt pans recall the enslaved salt workers, with Fort Oranje, Rincon's cunucu houses and the Arawak inscriptions at Onima for the rest.

Cozumel's past is Maya: the low, scattered temples of San Gervasio in the forested interior were part of a pilgrimage to the goddess Ixchel, and the waterfront museum fills in the island's history.

Cozumel has a little more life after dark, though neither island is for a big night out. San Miguel's waterfront and main square have cover bands, rooftop terraces and loud tequila bars, busiest in the late afternoon when cruise passengers are ashore, and the square fills with local families on Sunday evenings.

Bonaire offers a sunset drink at a waterfront bar in Kralendijk and the occasional weekend dance night, and then it is quiet well before midnight. On either island, anyone wanting clubs is out of luck, although from Cozumel the mainland is a ferry ride away.

Both are first-rate dive islands, but Bonaire offers more freedom in the water and more to do around it. Its entire coastline is protected, the reef begins just off the shore, and divers can make as many entries a day as they like from roadside stones without a boat. Lac Bay's steady trade winds over flat water draw windsurfers, and on land Washington Slagbaai, Brandaris and the flamingo-filled salt pans fill a day or two.

Cozumel's diving is boat-based and spectacular in its own way: currents carry divers along the coral walls of Palancar, Santa Rosa and Columbia past eagle rays and nurse sharks. Out of the water, the flat scrub island offers mainly Punta Sur's crocodile lagoons and a ride along the wild east coast.

This is where the two islands differ most. From Cozumel, the ferry to Playa del Carmen takes under an hour, and from there Tulum's cliff-top ruins, the cenote coast and the jungle city of Coba all fit into a long day, with organised tours to smooth the logistics.

Bonaire offers Rincon, seen in an hour, and a boat out to Klein Bonaire to snorkel. Curacao and Aruba need a flight, so on Bonaire the whole stay is spent on the island itself.

Cozumel is the easier island with children. Chankanaab's reef lagoon, sea lions and botanical garden, semi-submarine trips for non-swimmers and beach clubs with pools give families more to fill the days, and San Miguel's square has playgrounds in the evening.

Bonaire is safe and relaxed with very little traffic, and it is a wonderful place for older children learning to snorkel or dive. For younger ones it comes down to the shallow lagoon at Sorobon, the donkey sanctuary and flamingo spotting, and many swimming spots mean scrambling over coral rock.

On both islands a visitor relies on wheels rather than buses, but Bonaire makes self-driving simpler and more useful. Its quiet, well-kept roads lead to dive sites marked by painted stones, so a hired pickup turns the whole coast into a series of shore dives. Only the rough tracks in the national park call for a high-clearance vehicle.

Cozumel has one paved loop road and plentiful taxis on fixed zone fares, and dive operators usually collect guests from their hotels. Seeing the far side means renting a car or scooter for a day, and the mainland ferry leaves from the San Miguel pier.

Bonaire's shopping fits into a few streets of Kralendijk, while Cozumel's cruise port gives a browser far more to look at. On Bonaire that means dive gear, beachwear and some locally made art, enough to replace a lost mask or pick up a gift.

San Miguel's waterfront and the plazas by the piers are lined with duty-free jewellers, silver and tequila shops and stalls of hammocks, embroidered blouses and Mexican vanilla. The better-made pieces are in the small galleries on the side streets, away from the insistent sales pitch on cruise days.

Cozumel is the gentler island on the wallet, provided you stay in San Miguel and eat at the taco stands, the market and local seafood places. Its resorts and boat dives are priced for foreigners, and several days of diving add up fast.

On Bonaire nearly everything is imported, so meals and groceries cost more, most lodging is mid-range or upmarket, and car hire is almost unavoidable. Shore diving without a boat is the main saving.

Both islands are thin on performance, and the highlights are festivals rather than venues. Bonaire has Simadan, the harvest celebration of the north with its songs and dances, plus a small carnival.

Cozumel's pre-Lent carnival, one of the oldest in Mexico, fills San Miguel with parades and comparsa troupes, and mariachis play around the square during the rest of the year.

Rest on both islands comes from the slow pace rather than any spa culture, with treatments mostly inside resorts. Bonaire's calm is island-wide, with days set by sunrise dives and evenings ending early. On Cozumel the quiet is found away from the cruise piers, in the adults-only resorts on the southern hotel strip, on the empty east coast and in the occasional temazcal sweat lodge.