Aktun Chen Nature Park

The main event is a walk through a dry cave about 640 metres long, with a guide, a helmet and electric lighting picking out the formations. The route covers most of it and takes around an hour and a half. The name is Maya for a cave with a river inside, and that river is the second part of the visit: a swim with a snorkel in a cenote underground.

The park sits in about 400 hectares of forest some four kilometres south of Akumal, and also has zip lines and an animal rescue area. A guide, the safety gear and a locker come with entry; towels, food, drinks and photos do not, so bring cash. You need to be able to swim for the cenote, the cave is not wheelchair accessible, and children under five go only under an adult's direct watch. Hours run later in summer.