Blue Cave (Modra špilja)

The Blue Cave, known as Modra špilja, is a sea cave on the island of Biševo, a small island about five nautical miles south-west of Vis, and it is one of the best-known natural sights on the Croatian coast. Its fame rests on a daily display of light. Sunlight enters through an opening beneath the surface of the sea, passes through the water and is reflected from the white seabed inside the cave, so that the whole chamber glows with an intense blue and silver light. Objects in the water, including the hands of visitors and the paddles of the boat, shine as if lit from within. The effect is strongest in the hours around midday, when the sun is high, and the best time to see it is usually between about eleven in the morning and noon, in clear, calm weather.

The cave is often compared to the Blue Grotto on the island of Capri in Italy, which works in a similar way. Local fishermen on Biševo and Vis knew about the cave long before it became a tourist attraction, but it first reached a wider audience in 1884, when the Austrian painter and explorer Baron Eugen von Ransonnet-Villez visited it, described it and made it known to Europe. Today it is a protected natural monument and one of the main reasons that people visit Vis. The cave is small, and the chamber is only a few dozen metres across, so its effect comes from intensity rather than size.

The usual trip begins in the harbour of Komiža, on the western side of Vis, where organised excursions leave in the morning in order to arrive around midday. The boat ride across the channel takes about half an hour and gives views of the open sea and the rugged coast of Biševo, with its cliffs and small coves. Many tours combine the Blue Cave with swimming stops in clear bays, a visit to the Monk Seal Cave, and sometimes the Stiniva Cove and other places on Vis. At the cave, passengers transfer to small local rowing boats, which wait their turn at the entrance, and the entrance is a low, narrow opening. To pass through, visitors lie flat in the boat, and the boatman pulls it in, so people with claustrophobia or a fear of confined spaces may prefer to stay outside.

Practical points matter. Access depends on the weather and sea conditions, and trips may be cancelled when the swell is high, so it is wise to book flexibly and to have a backup plan. In July and August, the cave is crowded, and waiting times can be long, so going in the morning or in the shoulder season helps. A ticket is usually required for entry, in addition to the cost of the boat. Photography is possible, but the blue light is hard to capture, so it is better to enjoy it with your eyes. Swimming inside is often limited during peak hours.

The cave suits families, couples and travellers curious about natural wonders. Bring a swimsuit, a towel and sun protection.