The Full Form of DIAL is‍ Delhi International Airport.

Delhi Airport (IATA: DEL, ICAO: VIDP), also known as Indira Gandhi International Airport and IGI Airport, is the only airport serving the city of New Delhi. The Airport is the busiest one in India in terms of passenger traffic and cargo. 

The international Terminal 3 at the Indira Gandhi International Airport (IGIA) in New Delhi, India, was opened in July 2010. The IGIA is the busiest airport in the country handling close to 70 million passengers a year. It is also the busiest in South Asia and is expected to handle 100 million passengers by 2030.

The IGIA Terminal 3 (T-3) was built to facilitate the 2010 Common Wealth Games held in Delhi. Built at a cost of Rs128.5bn ($2.7bn), the 5.4 million square feet (502,000m²) terminal was reported to be the eighth largest in the world at that time. It can handle 34 million passengers a year.

Indira Gandhi airport is operated by Delhi International Airport (DIAL), a public-private consortium led by GMR Group. The stakeholders, GMR (54%), Airports Authority of India (26%), Eraman Malaysia (10%) and Fraport (10%), currently have the concession to operate the airport for 30 years.

IGIA handled approximately 69.23 million passengers, 460,424 aircraft movements, and 1,047 million tons of cargo in the financial year 2018-’19.

There are plans to continue to expand the airport if the traffic continues to grow. It is located in Palam, 16 km from the New Delhi city centre and 15 km south-west of New Delhi railway station. Indira Gandhi International Airport counts with three parallel runways.