The Nilgiri Mountain Railway runs from Mettupalayam to Udagamandalam (Ooty), via Coonoor. It's the only meter gauge, rack railway in India. Also known as a cog railway, it has a middle rail fitted with a rack that engages a pinion on the locomotive. This provides traction for the train to go up steep inclines. (Apparently, it's on of the steepest track in Asia, increasing from 1,069 feet to 7,228 feet above sea level). The train travels through the 208 curves, 13 tunnels and 250 bridges. And the architectural intelligence of bridges and stations are remain the same.How to book tickets:The tickets are booked through IRCTC website. IRCTC is an Indian railway website to book tickets. However the train tickets will be filled in 10 minutes of opening time it has a general unreserved compartment. The train has one unreserved compartment and other two reserved compartment. The tickets can be reserved by IRCTC website or by railway station booking counter. But the general unreserved tickets will be provided on the day of travel. If you are willing to travel through unreserved coach the you should be there in Mettupalayam railway station by 5 AM in the morning. There is a Queue in the 2nd platform which helps you to get the seats in the train. you will be given tokens then you can get the tickets and travel to ooty. The unreserved ticket costs around 15 rupees per person. Nearest city: Coimbatore.