1. Formation: The cave was formed by the erosive activity of the waters of the Iskar River over millions of years. The river still flows through the cave, dividing it into two chambers. 2. Unique Features: The most prominent feature of the cave is the two large openings on the cave ceiling, which resemble a pair of eyes when seen from a specific angle, hence the name "Eyes of God." These openings allow daylight to penetrate the cave, creating a stunning visual effect. The larger opening is about 45 meters high and 35 meters wide, while the smaller one measures around 25 meters high and 10 meters wide. 3. Historical Significance: The cave has significant historical importance as it was inhabited by humans since ancient times. Various archaeological finds, including pottery and tools, have been discovered within the cave, dating back to the Paleolithic and Neolithic periods. 4. Trigrad Gorge Matchbox: The Eyes of God is part of a larger geological formation known as the Trigrad Gorge Matchbox. Covering an area of about 130 square kilometers, this natural marvel consists of numerous limestone cliffs, caves, and canyons. 5. Bats: The cave serves as a habitat for a number of bat species, including the greater mouse-eared bat, the serotine bat, and the lesser horseshoe bat. Researchers have recorded over 30 bat species within the cave system.

6. Filming Location: Prohodna Cave has been featured in several films and documentaries. It gained international recognition as a filming location for the 2007 movie "The Way Back," directed by Peter Weir. 7. Cliff Jumping: One of the popular activities associated with the cave is cliff jumping. Adventurous individuals have been known to jump from the rocky ledges into the cold waters of the Iskar River below, which is permitted under certain safety regulations. 8. Access and Facilities: The cave is easily accessible from Sofia, the capital city of Bulgaria, as it is situated only about 115 kilometers away. There is a parking lot near the cave entrance, and a short trail leads visitors to the main chamber. The site has facilities such as a visitor center, picnic areas, and restrooms.