Cova de s’Aigua.

Today we took a guided tour - the last of the season in English - of the water cave in Ciutadella. I've seen it before, but Simon hasn't, and was as entranced as I was at the shapes, mineral colours, stalactites and stalagmites, which are perpetually forming as the constant dripping affirms. The baby stalactites look like drinking straws, and it was so tempting to snap one off for a souvenir, but that is rightly a criminal offense so I resisted. Some of the big splodgy stalagmites under formation look like mounds of rice pudding, and tiny ones look like boiled eggs. The lake is still and perfectly clear until a drop lands in it (main picture), and contains a number of perfectly preserved human bones from the Neolithic era, when the original cave was probably used as a burial chamber. The inscription by Lieutenant Wickham was written in graphite, which has fused into the other minerals in the structure, making it permanent and him therefore in a sense immortal. The amazing colours in the rock formations are from the minerals in their composition, and prehistoric shell fossils indicate where the sea bed, now part of the roof, was when the cave was formed. More info if you're interested:

The Cova de s’Aigua is located in the center of Cala Blanca, a southern suburb of Ciutadella de Menorca. It is a natural cave which has an underground connection to the nearby sea, the cave lake contain brackish water and the level changes with the tides. It formed inside calcarenites and limestone from the Upper Miocene (Tartonian and Messinian). At Cala Blanca there are numerous similar caves, this is the only one which is open to the public. It was closed for many decades, but has been opened 2021 with new trails, LED light system and a special elevator for wheelchairs. There will be a second phase, the 2016 discovered nearby cave will be added to the route.
In the entrance are of the cave numerous remains like ceramic fragments and some small vases were discovered. They are thought to belong to the pre-Talayotic and Talayotic culture. They are very similar to those found in a nearby domestic-type structure, the naveta of Cala Blanca. This site was excavated in the 1980s and the pre-Talayotic findings were dated 1700 BC and the Talayotic findings about 1200 BC. However, there was no archaeological excavation in the cave, the item were collected during the examination of the cave for its suitability as a show cave. In the lake human skeletal remains can be seen, which belong to a burial area located on the other side of the lake.
The cave was known since prehistoric times, the oldest remains beneath the archaeological remains are graffities, the oldest from 1580. More inscriptions are from the 18th century, when Menorca was under British domination. There are numerous British names, like the "Lord Forbes governour 1717", or the "Lieutenant J. Wickhman of the British Grenadier Corps". The second has added two dates, he visited the cave twice, on May 10 and on June 17, 1717.