The city's metro service, which came into service in 2002, is air-conditioned, reliable, and state-of-the-art. With new stations and lines opening for service every few months, subway service is rapidly changing the face of the city. It's an inexpensive (starting at Rs. 8 per one-way trip) and convenient way to move between Connaught Place (Rajiv Chowk station), Lutyens' Delhi (Central Secretariat station), and Old Delhi (Chandni Chowk and Chawri Bazaar stations). For example, getting to Old Delhi from CP is three stops and takes about 15 minutes. There are currently six lines—red, yellow, blue, green, violet, and the airport express, which links the airport with the centrally located New Delhi stop, which is close to the New Delhi railway stop. The fare for the airport express is Rs. 150. Maps are available at the official tourist office and often at your hotel concierge desk. The Rajiv Chowk station is massive; ask for directions as you go.