Kataleh Khor Cave is one of the world’s beautiful caves and it is located at 165 km southwest of Zanjan. The entrance to the cave is situated on the southern slopes of the 2,000-meter high Saghizloo Mountain. The cave has flat walls with high ceiling and archeologists estimate the age of the cave at 30 million years. The entrance to Kataleh Khor resembles a crevice at the beginning and culminates in a triangular arch. Archeologists have made the entrance bigger and it currently stands at 1.5 meter high. In 1951, a veteran mountaineer from Zanjan, Asadollah Jamali discovered the mysterious cave and a team visited it the following year. Since 1993, structure have been constructed in the vicinity of the cave to host visitors. Special lights and projectors have been installed to help visitors to get a glimpse of the unknown world inside the cave.