Cancún, a sandbar that became a city

Cancún was a sandbar with a few dozen residents until 1970, when Mexico's tourism development agency picked it off a shortlist and started building; it is now the busiest arrival point in the country after Mexico City. The Zona Hotelera occupies a barrier island twenty-two kilometres long and bent like a number seven, with open Caribbean on one flank and the sheltered Nichupté lagoon on the other, which is why you can be swimming through surf at ten in the morning and paddling flat water at four in the afternoon. The colour of that water is the thing people struggle to describe and never manage to exaggerate. Playa Delfines, at the southern end, is public, wide and backed by a low dune with a viewpoint down the whole coast; just behind it stand the small columned ruins of El Rey, where iguanas outnumber visitors by a wide margin. Off Punta Nizuc, the underwater sculpture museum has set hundreds of concrete figures on the seabed at snorkelling depth, and coral is slowly taking them over. Ferries run all day from Puerto Juárez to Isla Mujeres, a low island of golf carts and shallow turquoise shelf at Playa Norte; between June and September boats go further out to swim alongside whale sharks feeding on plankton blooms. Downtown is where the city actually lives: Parque de las Palapas fills every evening with marquesitas, elotes and families, and Mercado 28 sells cochinita, hammocks and hard bargaining to anyone who walks in. The sea sits near twenty-eight degrees most of the year, December to April is dry and breezy, and the hurricane season runs June to November without usually costing more than a day. Cancún works best as a first or last stop rather than the whole trip.