Railway zone are: Eklakhi–Balurghat branch line New Bongaigaon–Guwahati section New Jalpaiguri–New Bongaigaon section Rangiya–Murkongselek section Guwahati–Lumding section Lumding–Dibrugarh section Silchar–Sabroom section Katihar–Siliguri section Katihar–Jogbani branch line Alipurduar–Bamanhat branch line New Jalpaiguri–Alipurduar–Samuktala Road line Barauni–Guwahati line Darjeeling Himalayan Railway The Darjeeling Himalayan Railway is maintained and governed under the responsibility of Katihar division. It ascends from New Jalpaiguri; the climb begins at Sukna, continues uninterruptedly to Ghum () and descends the final to Darjeeling. After independence, India's partition resulted in the isolation of the Northeast region. Consequently, the DHR was merged into Assam Railways, it was closed for the construction of the Assam–Bengal link line and one of its extension lines to Kishanganj was converted to metre gauge. DHR's other extension line to Kalimpong was washed away due to floods. On reopening, the DHR was merged with North Eastern Railway in 1952 and later into Northeast Frontier Railway in 1958. The DHR achieved worldwide fame for many reasons such as: A gateway to the Himalayas The tiny four-wheeled steam locomotives of the 19th century The curves, loops, "Z"s and steep grades crisscrossing the road An interest in DHR all along has ensured that it continues to operate notwithstanding very heavy losses. The steam locomotive is an icon of this Railway. Tindharia workshop has kept 13 locomotives surviving, some of which are over 100 years old and the youngest is about 70 years old. Timeline of DHR: 20 January 1948: Purchased by the Government of India 26 January 1948: Transferred to Assam Rail Link 26 January 1950: Transferred to Assam Railway 14 January 1952: Transferred to North Eastern Railway 15 January 1958: Transferred to Northeast Frontier Railway Major Trains Dibrugarh Rajdhani Express Dibrugarh-Kanyakumari Vivek Express Avadh Assam Express Agartala Rajdhani Express Bangalore Humsafar Express Agartala - Firozpur Tripura Sundari Express Aronai Superfast Express Dibrugarh-Chandigarh Express Dibrugarh-Amritsar Express Dwarka Express Amarnath Express Kamakhya–Shri Mata Vaishno Devi Katra Express Kamakhya - Lokmanya Tilak Terminus Karmabhoomi Express Kamakhya - Udaipur City Kavi Guru Express Kamakhya - Dr. Ambedkar Nagar Express Kamakhya–Gandhidham Superfast Express Dibrugarh– Chennai Tambaram Express Dibrugarh - Mumbai LTT Express Loco sheds Diesel Loco Shed, Siliguri Diesel & Electric Loco Shed, Malda Town Diesel Loco Shed, New Guwahati Diesel Loco Shed, Mariani Sicklines & Pitlines Dibrugarh Coaching Depot, Dibrugarh Pitline, Dibrugarh N.F.Railway Mechanical Workshop, Dibrugarh Coach Maintenance Depot/Sickline, Guwahati Pitline, Guwahati Pitline, New Guwahati New Bongaigaon Carriage & Wagon Workshop, New Bongaigaon Coach