Bordering the Gulf of Mexico, around 100km north of Valladolid, Río Lagartos National Park offers the chance year-round to spot several species of migratory birds and a colony of pink flamingoes. A 2hr boat trip will take you through the mangroves as far as Las Coloradas, where salt ponds are mined. On the way back, you can stop off to test the benefits of a clay bath. The beach of the small village of San Felipe also attracts bathers.