the bolan tunnel is a hole through the toba sudhir mountains of mountainous on the border of pakistan . the british took the threat of a mughal invasion of india by the himalayas and recchi passes very seriously so in 1837 , a british envoy was sent to pakistan to gain supporting of the emir , dost hassan . in february of 1839 , the british army under sir john keane had 12 , 000 soldier through the bolan range and entered kandahar .
The British Army crossed the Toba Kakar Range of mountains in 1839.