Question: What is the name of the airport in the region that contains Củ Chi tunnels?

full_context: Document 1: Military history of the United States: The Vietnam War was a war fought between 1959 and 1975 on the ground in South Vietnam and bordering areas of Cambodia and Laos (see Secret War) and in the strategic bombing (see Operation Rolling Thunder) of North Vietnam. American advisors came in the late 1950s to help the RVN (Republic of Vietnam) combat Communist insurgents known as "Viet Cong." Major American military involvement began in 1964, after Congress provided President Lyndon B. Johnson with blanket approval for presidential use of force in the Gulf of Tonkin Resolution.
Document 2: Tan Son Nhat International Airport: Tân Sơn Nhất International Airport (IATA: SGN, ICAO: VVTS) (Vietnamese: Sân bay quốc tế Tân Sơn Nhất, Vietnamese: Cảng hàng không quốc tế Tân Sơn Nhất) is the busiest airport in Vietnam with 32.5 million passengers in 2016, serving Ho Chi Minh City as well as the rest of southeastern Vietnam. As of January 2017, it had a total capacity of only 25 million passengers, which has caused constant congestion and sparked debate for expanding or building a new airport. The airport's IATA code, SGN, is derived from the city's former name of Saigon.
Document 3: Củ Chi tunnels: The tunnels of Củ Chi are an immense network of connecting tunnels located in the Củ Chi District of Ho Chi Minh City (Saigon), Vietnam, and are part of a much larger network of tunnels that underlie much of the country. The Củ Chi tunnels were the location of several military campaigns during the Vietnam War, and were the Viet Cong's base of operations for the Tết Offensive in 1968.
Document 4: Vietnam Airlines: While the airline had launched flights to London-Gatwick, Beijing and Shanghai, as of April 2018 there are no flights to Mumbai, Doha, and Brisbane. The airline also plans to re-open flights to Berlin, and commence flights to Adelaide, Perth, Amsterdam, Milan, Prague, Mandalay, Dalian, Nanjing, Hangzhou and African cities; by 2020, Vietnam Airlines is expected to serve 53 international destinations, up from 27 in 2011. By 2020, Vietnam Airlines plans to increase its annual revenue to US$7 billion – up from $1.86 billion in 2010 – by carrying 620,000 tonnes of cargo and 35 million passengers, using a fleet of 163 aircraft (later revised to 41 million passengers using 170 aircraft). It aims to capture a 45% market share of Vietnam's aviation market. During its first 15 years of operation, from 1996 to 2010, Vietnam Airlines carried a total of 82 million passengers on 678,550 flights. In addition, Vietnam Airlines plans to transfer most of its international operations from its current hub, Tan Son Nhat International Airport, to the proposed Long Thanh International Airport. With a cost of approximately US$6 billion, the airport will, according to Vietnamese authorities, help Vietnam Airlines boost its operations internationally as it seeks to bypass Thailand as the dominant gateway to the Greater Mekong region. London operations were transferred from Gatwick to Heathrow in 2015; the airline plans to operate its new Boeing 787-9 aircraft to this destination, starting from .
Document 5: Leaders of the Vietnam War: Ho Chi Minh was the key figure and held the main leadership of North Vietnam during both wars in the country. He remained as a great source of inspiration for the Vietnamese who were fighting for a united Vietnam as in his wish after he officially stepped aside in 1965 and even after his death in 1969. The final offensive against Saigon -- the capital of South Vietnam in 1975 was named after him (the Ho Chi Minh Campaign). Vietnam was reunified under the Communist rule after the fall of Saigon in April 1975, nearly 30 years after Ho's declaration of independence and 6 years after his death. Soon after that, Saigon was renamed Ho Chi Minh city in honour of his vast contributions to Vietnam.
Document 6: Ho Chi Minh City: Ho Chi Minh City Thành phố Hồ Chí Minh Saigon or Sài Gòn Municipality Thành phố trực thuộc trung ương Clockwise, from left to right: Bến Thành Market, Ho Chi Minh City Hall, District 1 view from Saigon river, Municipal Theatre, Notre - Dame Cathedral Basilica of Saigon, Independence Palace Seal Nickname (s): Pearl of the Far East Location in Vietnam and Southern Vietnam Coordinates: 10 ° 46 ′ 36.8 ''N 106 ° 42 ′ 02.9'' E ﻿ / ﻿ 10.776889 ° N 106.700806 ° E ﻿ / 10.776889; 106.700806 Coordinates: 10 ° 46 ′ 36.8 ''N 106 ° 42 ′ 02.9'' E ﻿ / ﻿ 10.776889 ° N 106.700806 ° E ﻿ / 10.776889; 106.700806 Country Vietnam Central district District 1 Founded as Gia Định 1698 Renamed to Ho Chi Minh City 1976 Founded by Nguyễn Hữu Cảnh Divisions 19 Urban districts, 5 Suburban districts Government Type Special - class Secretary of Communist Party Nguyễn Thiện Nhân Chairman of People's Committee Nguyễn Thành Phong Chairman of People's Council Nguyễn Thị Quyết Tâm Area Total 2,096.56 km (809.23 sq mi) Elevation 19 m (63 ft) Population (2016) Total 8,426,100 Rank 1st Density 4,000 / km (10,000 / sq mi) GDP (PPP) (2015 estimate) Total US $127.8 billion Per capita US $15,977 GRDP (nominal) (2016) Total US $45.73 billion Per capita US $5,428 Time zone ICT (UTC + 07: 00) Area codes 8 (until 16 Jul 2017) 28 (from 17 Jun 2017) Website hochiminhcity.gov.vn
Document 7: Museum of Vietnamese History: The Museum of Vietnamese History is located at 2 Nguyen Binh Khiem Street, Ben Nghe Ward, District 1, in Ho Chi Minh City, Vietnam. Formerly known as the Musée Blanchard de la Brosse, built by Auguste Delaval in 1926, and The National Museum of Viet Nam in Sai Gon, it received its current name in 1979. It is a museum showcasing Vietnam's history with exhibits from all periods. It should not be confused with the National Museum of Vietnamese History in Hanoi. The topics covered by the exhibits include the following:
Document 8: Côn Đảo Prison: Côn Đảo Prison (), also Côn Sơn Prison, is a prison on Côn Sơn Island (also known as Côn Lôn) the largest island of the Côn Đảo archipelago in southern Vietnam (today it is in Bà Rịa–Vũng Tàu Province. The prison was built in 1861 by the French colonists to jail those considered especially dangerous to the colonial government. Many of the high-ranking leaders of Vietnam were detained here. It is ranked a special historical relic of national importance by the government of Vietnam. The most famous site in this prison are the "tiger cages" (vi:"chuồng cọp"). The French tiger cages cover an area of 5.475 m, within which each cell occupies 1.408 m, solariums occupy 1.873 m, and other spaces occupy 2.194 m. The prison includes 120 cells.
Document 9: Mumbai: The Chhatrapati Shivaji International Airport (formerly Sahar International Airport) is the main aviation hub in the city and the second busiest airport in India in terms of passenger traffic. It handled 36.6 million passengers and 694,300 tonnes of cargo during FY 2014–2015. An upgrade plan was initiated in 2006, targeted at increasing the capacity of the airport to handle up to 40 million passengers annually and the new terminal T2 was opened in February 2014.The proposed Navi Mumbai International airport to be built in the Kopra-Panvel area has been sanctioned by the Indian Government and will help relieve the increasing traffic burden on the existing airport.The Juhu Aerodrome was India's first airport, and now hosts the Bombay Flying Club and a heliport operated by state-owned Pawan Hans.
Document 10: New Delhi: Indira Gandhi International Airport, situated to the southwest of Delhi, is the main gateway for the city's domestic and international civilian air traffic. In 2012-13, the airport was used by more than 35 million passengers, making it one of the busiest airports in South Asia. Terminal 3, which cost ₹96.8 billion (US$1.4 billion) to construct between 2007 and 2010, handles an additional 37 million passengers annually.
Document 11: Saigon Bridge: Saigon Bridge, known as Newport Bridge () before 1975, is a bridge crossing the Saigon River, connecting Bình Thạnh District and District 2, Ho Chi Minh City, on the Hanoi Highway. The bridge has four lanes for cars and two lanes for motorcycles and bicycles. It was the only bridge linking District 1 to the new Thu Thiem New Urban Area in District 2 until the Thủ Thiêm Bridge opened in 2008 and the Saigon River Tunnel opened in 2011. The bridge was one of the most vital gateways for vehicles traveling from northern and central Vietnam to the city, and therefore was a key point of contention during the Tet Offensive in 1968 and the Fall of Saigon in 1975. In 2013, a new parallel bridge, Saigon 2 Bridge, was opened to ease congestion on the bridge.
Document 12: Mobile Riverine Force: In the Vietnam War, the Mobile Riverine Force (MRF) (after May 1967), initially designated Mekong Delta Mobile Afloat Force, and later the Riverines, were a joint US Army and US Navy force that comprised a substantial part of the Brown Water Navy. It was modeled after lessons learned by the French experience in the First Indochina War and had the task of both transport (of soldiers and equipment) and combat. The primary base was at Đồng Tâm Base Camp, with a floating base at the base of the Mekong River. It played a key role in the Tet Offensive.
Document 13: Bình Hưng Hòa Cemetery: Binh Hung Hoa Cemetery () was formerly the largest cemetery in the urban area of Ho Chi Minh City. It was located in the suburban outskirts of the city but due to the rapid urbanization of Ho Chi Minh City, the urban area eventually eclipsed the cemetery. There are several illegal houses built in and around the cemetery, and an estimated 300,000 residents live among the tombs. In Vietnamese custom, the dead are often buried and therefore puts the pressure on land near the city, especially a large city like Ho Chi Minh City.
Document 14: 2008 Summer Olympics torch relay: Vietnam: The event was held in Ho Chi Minh City on April 29. Some 60 torchbearers carried the torch from the downtown Opera House to the Military Zone 7 Competition Hall stadium near Tan Son Nhat International Airport along an undisclosed route. Vietnam is involved in a territorial dispute with China (and other countries) for sovereignty of the Spratly and Paracel Islands; tensions have risen recently[when?] following reports that the Chinese government had established a county-level city named Sansha in the disputed territories, resulting in anti-Chinese demonstrations in December 2007 in Hanoi and Ho Chi Minh City. However to sustain its relationship with China the Vietnamese government has actively sought to head off protests during the torch relay, with Prime Minister Nguyễn Tấn Dũng warning government agencies that "hostile forces" may try to disrupt the torch relay.
Document 15: Seoul: Incheon International Airport, opened in March 2001 in Yeongjong island, is now responsible for major international flights. Incheon International Airport is Asia's eighth busiest airport in terms of passengers, the world's fourth busiest airport by cargo traffic, and the world's eighth busiest airport in terms of international passengers in 2014. In 2016, 57,765,397 passengers used the airport.
ground_truth: Tân Sơn Nhất International Airport
sub_queries: Củ Chi tunnels >> located in the administrative territorial entity Answer: Ho Chi Minh City
what is the name of the airport in Ho Chi Minh City Answer: Tân Sơn Nhất International Airport