Delhi's Indira Gandhi International Airport grew from Palam airfield, built in the 1930s and used heavily by the Allies during the Second World War before becoming the capital's civil airport, replacing the small Safdarjung aerodrome in 1962. A new international terminal opened in 1986, when the airport was renamed for assassinated prime minister Indira Gandhi. For decades Palam's modest facilities strained under India's growing traffic.
Transformation came after 2006, when a consortium led by GMR Group took over under a modernization concession. The colossal Terminal 3, opened in 2010 ahead of the Commonwealth Games, was then one of the largest airport terminals in the world, an eight-level building with capacity for 34 million passengers that vaulted Delhi into the global first tier.
Subsequent years brought a third runway, then in 2023 a fourth runway and an elevated taxiway, making Delhi the first Indian airport with four runways. IGI overtook Mumbai as India's busiest airport and now ranks among the ten busiest in the world, handling over 70 million passengers a year as the main hub for Air India and IndiGo, with an expanded Terminal 1 and long-term plans pushing capacity beyond 100 million.