Lençóis Maranhenses

The rain arrives between January and May, and then it sits there. Water gathers in the hollows between the dunes and spreads, in the Maranhão environment secretariat's own words, across practically the whole area of the park, so that by June there are thousands of freshwater lagoons in a field of white sand. By November most of them have gone again, and the ones still holding water are the perennial few.

UNESCO inscribed this as a Natural World Heritage site on 26 July 2024, at the 46th session of the World Heritage Committee in New Delhi. Getting in costs nothing, because ICMBio charges no visitation fee at all, and the park is open every day of the year; what you pay for is the accredited driver, the accredited vehicle and the accredited guide, all three of which are required. You cannot drive yourself: motorised transit across the open dune field is prohibited outright, and private cars, motorbikes, buggies, quad bikes and UTVs are barred unless ICMBio authorises them individually. Four towns open onto the park, Barreirinhas, Santo Amaro do Maranhão, Humberto de Campos and Primeira Cruz, with São Luís and Parnaíba the airports behind them. The pressure is now the story: visits went from 141,000 in 2019 to 440,000 in 2024, Santo Amaro alone from 61,000 in 2021 to 297,000, and ICMBio has been working with the municipalities and local communities to establish what flow the sand can take before any cap is set.