Cave Koretanac, near the city of Knjazevac, is known source cave length of 1441m. The present length is credit of club SAIS. Estimation of all explored channels is approximately 1600m. We were invited to participate in further explorations of terminal sumps by the SAIS club. The cave entrance is close to the road and with moderate access. After the entrance, moving throughout dry channels is starting to be tricky. A lot of tight places, deep water, verticals and traverses where rope is needed.
After short transport to the first sump, we decide to bypass it via dry channels and go right to the known terminal sump. When SAIS members checked this sump few days ago, it was crystal clear but due the rains last day, visibility changed drastically.
Since we were already there and equipment was brought, there was no reason not to try at least. Upon entry mudslide limited visibility in that part to none. Finding way further was challenging but manageable. It was a horizontal crack, wide enough to squeeze through with 2x7l steel tanks. On the other side was a wider chamber with a slope going steeply down. Max recorded depth is -24 meters, but there were seen deeper parts of the chamber. Visibility in the chamber shortly matched the first part due the exhaled air, which hit the roof and with it deposited sediment. After some time spent there and not finding way further, it was time to start way back.