The North Western State Railway (reporting mark NWR) was formed in January 1886 from the merger of the Scinde, Punjab & Delhi Railway, the Indus Valley State Railway, the Punjab Northern State Railway, the eastern section of the Sind-Sagar Railway, the southern section of the Sind-Pishin State Railway and the Kandahar State Railway. The NWR also absorbed several smaller railways, including the Quetta Link Railway (a strategic line constructed by the Scinde, Punjaub & Delhi Railway in 1887), Jammu-Sialkot Railway (opened in 1897), Kasur-Lodhran Railway (opened 1909-10 and later dismantled), Shorekot Road-Chichoki Railway (opened 1910), Sialkot-Narowal Railway (opened 1915), Shahdara Bagh-Narowal Railway (opened 1926) and the Trans-Indus Railway (opened 1913). The military and strategic concerns for securing the border with Afghanistan were such that Francis Langford O'Callaghan, who was posted from the state railways as engineer-in-chief, was called on for a number of demanding railway projects, surveys and constructions in the Northwest Frontier. What began as military and strategic railway projects became part of the North Western State Railway network at its formation in 1886. The Bolan Pass railway was completed in 1886, and the 1887 Khawaja Amran Railway Survey included the Khojak Tunnel and the Chaman Extension Railway. The Khojak Tunnel opened in 1891 and the railway reached Chaman, near the Afghan border. By 1905, it was the longest railway under one administration and the strategic railway of the Northwest Frontier. In 1947, much of the North Western State Railway in Pakistan became part of Pakistan Western Railways; the Indian portion was incorporated into the Eastern Punjab Railway.