Tora Bora (Pashto: توره بوړه‎, Black Cave), known locally as Spīn Ghar (Pashto: سپین غر‎, White Mountain), is a cave complex situated in the Safēd Kōh of eastern Afghanistan, in the Pachir Aw Agam District of Nangarhar, approximately 50 km (31 mi) west of the Khyber Pass and 10 km (6.2 mi) north of the border of the Federally Administered Tribal Areas in Pakistan. Tora Bora was known to be an important area for the Taliban and insurgency against the Soviet Union in the 1980s. Tora Bora and the surrounding Safēd Kōh range had natural caverns formed by streams eating into the limestone.