New Delhi, Oct. 23 -- India is stepping up efforts to manufacture advanced tunnel boring machines (TBMs) domestically as it expands its infrastructure network, with the 125-km Rishikesh-Karnaprayag railway line highlighting the scale of engineering required to build through the Himalayas.

Railway Minister Ashwini Vaishnaw said India is now manufacturing TBMs with diameters of 8 metres and 15 metres and plans to produce machines exceeding 16 metres. The development comes amid fresh Chinese restrictions on TBM exports, highlighting the importance of domestic manufacturing for infrastructure projects that require specialised tunnelling equipment, according to The Economic Times.

The push forms part of a broader effort to develop domestic c...