Answer: Haryana and Himachal Pradesh
Notes: The Himachal Pradesh Chief Minister urged the Central government to consider running green hydrogen trains on the Kalka-Shimla Railway (KSR). KSR is a narrow-gauge railway from Kalka (Haryana) to Shimla (Himachal Pradesh). It was built in 1898 to connect Shimla, then the British summer capital, to the Indian rail network. The 96 km line, opened in 1903, is known as the "toy train" and includes 18 stations, 102 tunnels, and over 850 bridges. The line climbs from 655 m to 2,076 m altitude, showcasing remarkable engineering with the Kanoh multi-arch bridge and Barog tunnel. Designated a UNESCO World Heritage Site in 2008, it holds a Guinness World Record for its steep ascent.
