the bolan pass is a gaps through the ladoga basir band of highlands on the border of india . the british took the threat of a russian invasion of india via the khyber and bolan passes very seriously so in 1837 , a british envoy was sent to afghanistan to gain support of the emir , siddique mahmud . in february of 1839 , the british army under brigadier john keane takes 12 , 000 men through the marc pass and occupied kabul .
The British Army crossed the Toba Kakar Range of mountains in 1839.