Cova de S'Aigua

The underground lake is what people come away talking about: still, dark water at the end of the route, with the village going about its day somewhere overhead. Getting there is a run of stops, each one with something for the guide to point out, and the guides carry the visit as much as the cave does — knowledgeable, and light enough with it that children stay interested for the full hour.

From the street none of this shows. People walk past the door without knowing anything is under there, which is part of the pleasure of turning up at an ordinary village address and being taken down.

• Book ahead. Tours leave at set times and run at around a dozen people, so turning up on spec can mean a wait or no place at all.
• An English-language tour may not be running. Tours go in set languages on set days — check before you travel, especially if you are coming by bus.
• Closures are not always posted online. The cave has shut at short notice for technical work with nothing on the website to warn anyone off.
• No drinking water nearby — bring a bottle. Toilets are on site for visitors, with public ones about 300 m away.
• Cards work. Credit cards, debit cards and contactless are all accepted.

Cala Blanca is a spread of holiday blocks and villas, and the cave sits in among them on a residential street: no track, no walk across open ground. A bus stop named Cova de S'Aigua is about 88 m away in a straight line, with another about 250 m off, so the last stretch is along village streets.

Two car parks lie about 160 m and 190 m away in a straight line. Once you are at the door the journey is over — everything after that happens inside, down to the lake and back.

Best: the morning. Tours start early and the cave is finished with its day by the early afternoon, which leaves the rest of it free for the beach.

Avoid: arriving mid-afternoon, by which time the last tour has gone.

Weather makes no difference underground, so this is the obvious call on a grey or windy day when the coast is out of the question.

Entry is on a guided tour only, at set times — there is no self-guided route through the cave. The group stays with the guide from the door, through the stops, down to the lake and back out the same way, which also means the pace is not yours to set.