The Kalka-Shimla Railway is a UNESCO World Heritage Site and one of the great mountain railway journeys in Asia — 96 kilometres of narrow-gauge track climbing from Kalka in the Punjabi foothills (656 metres) to Shimla (2,076 metres) through 102 tunnels, across 864 bridges, and around curves that reduce speed to a crawl in the steepest sections. The journey takes 5–6 hours on the regular service, slower on the heritage tourist trains, and the views through the windows are extraordinary — pine forests, Himalayan foothills, and the steep valleys of the Shivalik range.
The toy train (as it is universally called) departs from Kalka station, which connects to the main Delhi-Chandigarh rail corridor. Several trains run daily in each direction; the Shivalik Deluxe Express and the Himalayan Queen are the most comfortable services. Taking the train up and returning by road — or vice versa — gives the best of both experiences. The journey is as much the point as the destination; book in advance, particularly on weekends and in peak season.