Originally known as the "Trans–Baluchistan Railway", the line was built as part of a strategic military route between British India (specifically the part now Pakistan) and Persia (now Iran). The Quetta to Nushki branch was approved by Lord George Hamilton, Secretary of State for India, in August 1902, and it was opened on 15 November, 1905. The part west of Nushki towards Iran was named the Nushki Extension Railway. Work started on it in September 1916 under the charge of P.C. Young as Engineer-in-Chief and it reached the Iranian town of Duzdap (now Zahedan, a small city) on 1 October, 1922. By the time the railway reached Duzdap, the British had already demobilized their forces in East Persia in March 1921 which took away the importance of the newly built part. So much so that in 1931, the 221–kilometer section between Nok Kundi and Duzdap (Zahedan) was closed and track removed to be used elsewhere. World War II however, renewed interest in the Quetta-Zahedan link. British forces wanted to aid the Soviet forces by supplying material through Persia. Aid through Persia proved unnecessary (due to successful Arctic convoys of World War II and similar supplies) but the Quetta-Zahedan link was reopened on 20 April 1940 in Zahedan.