Public Transportation  from Delhi Indira Gandhi Airport to your destination:  (You can rent a car from 'carzonrent' (tel. 91 11 41841212 or toll-free 1860-500-1212); or take a taxi (Easy Cabs, tel. 43434343, at International & Domestic Arrivals, and Meru Cabs, tel. 44224422, at Domestic Arrivals) - counters for booking are inside the Arrivals halls). 

(a) The passenger complex is connected via a dedicated Delhi Metro Railway Line encompassing the whole of New Delhi. Trains run presently every 12 mins, 6am to 10pm. Each of the Delhi Metro stations have their own parking spaces. 
(b) Terminal 3 has a high-speed rail link to city center - the new Airport Express has presently 4 stations: New Delhi (the metro station is adjacent to Ajmeri Gate side of the ND Railway station), Shivaji stadium, Indira Gandhi  Airport, & Dwarka sector 21 (Dhaula Kuan, and Delhi Aerocity or NH8 stations will follow later). Trains run every 10 minutes at up to 105 km/ph and take 20 minutes. 
(c) The Shatabdi Express trains departs New Delhi railway station starting 4:45am, with increased frequency during rush hours - every ten minutes 30 seconds & at non-rush hours every 15 minutes.

NOTE:  Passengers on Airport Express line wishing to board the Delhi Metro train from New Delhi Metro station may now purchase tokens & smart cards at the Airport Metro Station for onward travel to the New Delhi station of the Yellow Line to other Metro Lines.  (The Yellow Line operates from HUDA City Center in Gurgaon to Jaangirpuri in north Delhi.
To view the Delhi Urban Rail expansion plan map open map https://www.google.com/maps/d/viewer?mid=zUj1ihMbzw_0.kbI-AtW--zMg&hl=en&ie=UTF8&msa=0&z=10

Air-conditioned GPS-equipped buses start from ISBT Kashmere Gate, ISBT Anand Vihar, Noida & Rohini, make multiple stops the first few kilometers - and then speed up to the Airport. 

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