Solution:The Mountain Railway of India consists of five railway lines built in the mountains of India. These are:1. Darjeeling Himalayan Railways
2. Nilgiri Mountain Railways
3. Kalka-Shimla Toy Train
4. Matheran Hill Railways
5. Kangra Valley Railways
Three of the mountain railways of India - the Darjeeling Himalayan Railway, the Nilgiri Mountain Railway and the Kalka - Shimla Railway are jointly listed as a UNESCO World Heritage Site under the name of "Mountain Railways of India." The fourth railway, the Matheran Hill Railway, is on the UNESCO World Heritage Sites tentative list.