Digboi Oil Refinery Railway
Oil had been discovered in 1866 by a Mr Goodenough of McKillop, Stewart & Co and a concession was granted November 1866, at Nahorpung about 30 miles (48 km) south east of Digboi. The AR&TC had found oil coming to the surface while constructing the Dibru-Sadiya Railway between Dibrugarh and Margherita in 1867  and were granted a concession. At this time the AR&TC was more interested in the building of the railway and developing its collieries .
In 1889 oil was struck at Digboi by the AR&TC and they constructed the Digboi station on their Dibru-Sadiya Railway, in 1892 another strike was made and by 1893 the boundry of the company's land was agreed with the Government. A small refinery was built at Margherita. By 1893 there were six wells producing oil. In 1899 AR&TC promoted a new company Assam Oil Company, which was sold to Burmah Oil Company in 1921 .
The records show that MG locomotives locomotives were supplied to the Digboi Refinery operation from 1896 onwards . The extent of the track has not been determined.