Blue Cave | Split

Information

Landmark: Blue Cave
City: Split
Country: Croatia
Continent: Europe

Blue Cave, Split, Croatia, Europe

The Blue Cave (Modra špilja) is a water-logged sea cave situated in Balun Bay on the eastern coast of Biševo Island. Though frequently accessed via speedboat tours departing from Split, the site is geographically located 5 kilometers southwest of the island of Vis in the central Dalmatian archipelago.

Visual Characteristics

The grotto is a geomorphological limestone formation measuring 24 meters in length, 15 meters in height, and up to 12 meters in depth. Its primary visual feature is a luminous azure glow produced by sunlight entering through a large submerged opening and reflecting off the white sandy and limestone seabed. Objects submerged in the water take on a silver or iridescent appearance due to the refraction of light through the high-clarity Adriatic water.

Location & Access Logistics

The cave is approximately 70 kilometers (38 nautical miles) from Split. Direct access from Split is primarily via organized 90-minute speedboat tours departing from the Riva Promenade or Matejuška pier. Travelers must transfer to small, 12-passenger motorboats at Mežuporat Cove on Biševo, as the cave’s artificial entrance is only 1.5 meters high and 2.5 meters wide. Independent travelers can take a 2.5-hour ferry from Split to Vis, a bus to Komiža, and then a local boat to Biševo.

Historical & Ecological Origin

The cave was originally accessible only by diving until 1884, when an artificial entrance was blasted into the rock following a suggestion by Austrian explorer and artist Baron Eugen von Ransonet. It is a semi-submerged sea cave formed by wave erosion in Cretaceous limestone. The site is a protected natural monument and part of the UNESCO Global Geopark Vis Archipelago, supporting a specialized ecosystem of shade-dwelling marine organisms.

Key Highlights & Activities

Activity is limited to passive viewing from authorized shuttle boats; swimming and diving inside the cave have been strictly prohibited since 2014 to preserve the ecosystem. Visitors typically spend 10–15 minutes inside the grotto. Most tours from Split combine the visit with stops at the Monk Seal Cave, Stiniva Cove, and the town of Hvar.

Infrastructure & Amenities

Mežuporat Cove serves as the logistical hub, featuring a ticket office, a small gift shop, a snack bar, and public restrooms. There are no facilities or shade at the cave entrance itself. 4G/5G cellular signals are generally available on the island but weaken inside the limestone structure. Visitors wait for their entrance number at the Mežuporat lounge area, which offers limited seating and a nearby pebble beach.

Best Time to Visit

The peak luminous effect occurs between 11:00 AM and 1:00 PM when the sun reaches its highest point, allowing maximum light to penetrate the underwater opening. For photography, bright sunny days are essential; cloudy conditions significantly diminish the blue intensity. The cave is frequently closed during South winds (Jugo), which create swells that make the narrow entrance impassable.

Facts & Legends

While the cave is often compared to Italy’s Grotta Azzurra, Baron von Ransonet famously claimed the Biševo cave’s lighting was superior due to the specific white-sand floor. A stone bar connecting the cave walls is visible just below the waterline, appearing as a glowing silver bridge in the peak midday light.