Scientists have explained the bright blue glow of the Capri sea cave

The blue grotto of Capri, the water in which literally glows with a bright blue light, may seem more like the fruit of artificial illumination or even the result of the work of a software photo editor. But the cause of the phenomenon is completely natural.

Daylight penetrates not only through the entrance to the grotto, through which small rowing boats can sail, but also through another, underwater hole. During most of the day, light can make its way through this flooded entrance, illuminating the water from below and creating this shining blue effect.

The grotto has been admired for thousands of years. It is said to have been the private bathhouse of Tiberius, the second Roman emperor, who ruled from 14 to 37 AD.

Three statues depicting Neptune and other Roman mythological characters were discovered on the seabed of the cave in 1964, indicating that in ancient times it could also have been used as a temple.

Several more bases of the statues were discovered in 2009 during archaeological surveys. After the discovery, the researchers said that it was consistent with the report of the Roman scientist Pliny the Elder (23-79 AD), who described the sea cave as the haven of the water demigod Triton.