In September 2025, Prime Minister Narendra Modi inaugurated Mizoram’s first railway line, the Bairabi–Sairang broad-gauge railway spanning 51.38 km, connecting Bairabi on the Assam–Mizoram border to Sairang, 20 km from Aizawl. What challenging feature marks 54% of this route's alignment?

The correct answer is Tunnels and bridges. In News Mizoram’s first railway line, Bairabi–Sairang (51.38 km), inaugurated by PM Modi; 54% alignment through tunnels and bridges, costing Rs 8,070 crore. Key Points The 51.38 km broad-gauge line connects Bairabi (Assam border) to Sairang (20 km from Aizawl), making Aizawl the fourth NE capital with rail links after Guwahati, Agartala, Itanagar. Project sanctioned in 2008-09, construction started 2015; features 45 tunnels, 55 major bridges, 87 minor bridges, navigating Northeast's hilly terrain effectively. 54% of alignment runs through tunnels and bridges, showcasing advanced engineering to overcome steep gradients and unstable geology in Mizoram's challenging landscape. Bridge No. 144 near Sairang is India's tallest pier railway bridge at 114 metres, a key highlight of the infrastructure marvel. Total cost reached Rs 8,070 crore, funded under national rail connectivity projects for economic integration of remote Northeast regions. Inauguration boosts passenger and freight movement, reducing travel time to Aizawl and spurring tourism, trade, and development. Line enhances Northeast's strategic connectivity, aligning with India's Act East Policy for balanced regional growth. Additional Information Mizoram became India's 28th state in 1987; rail connectivity long overdue. Broad gauge (1,676 mm) is India's standard for high-speed, heavy-load rails. NE states now have improved multi-modal links via rail, road, air. Project executed by N.F. Railway under IRCON and RVNL. Aizawl elevation (1,132 m) demanded specialised tunnelling tech.