Cave Biserujka is the underground pearl of the island of Krk. It is located in the northeastern part of the island, near the village of Rudina. About 100 meters from the cave there is a parking lot.
The cave is open for tours from April to October. In July and August, the working hours are from 9 am to 6 pm. Tickets can be purchased at the house in the immediate vicinity of the cave. A guided tour of the cave takes about 15 minutes. Cave Biserujka can only be visited by a limited number of people at a time, so individual guests have to wait a long time to visit the cave in the case of larger groups. There are various information boards around the cave. The cave was discovered about 100 years ago. There was a widespread legend among the people that there were smuggled goods in the cave and hence the name. Cave Biserujka is 110 meters long. Throughout the year, the air temperature in the cave ranges between 10 and 13 degrees Celsius. The underground galleries are full of picturesque stalagmites, calcite pillars and stalactites. The cave is given special value by the endemic crab Alpioniscus christiani (Krcka spiljska babura), which is its only habitat in the whole world. It was renovated in 1997, when illuminated paths were arranged for visitors, enabling an interesting visual experience.
Although the cave is short in length, it leaves no one indifferent. Next to the Cave Biserujka there is an educational trail that leads from the cave to the Slivanjska Bay and lasts about half an hour.