Vandalur zoo In 1854, Dr. Edward Balfour, then director of the Government Central Museum at Madras, persuaded the Nawab of the Carnatic to donate his entire animal collection to the museum. This attracted large crowds and became the nucleus of the Madras Zoo,

which was founded in 1855. Dr. Belford started the zoo on the museum premises, and it was later transferred

to the Madras Corporation and shifted to 'People’s Park' near Central station at Park Town in 1861 as it was growing. The municipal zoological garden occupied one end of the 116-acre (47 ha) park and was open free to the public.[12][13]

By 1975, the zoo could no longer expand, and it had to be moved out of the city because of space constraints and increased noise pollution due to the city's high-density traffic. Hence a plan was prepared in 1976 to maintain these animals in good simulated condition. In 1979, the Tamil Nadu Forest Department set aside 1,265 acres (512 ha) in the Vandalur Reserve Forest on the outskirts of the city to build the current zoo, which is the largest zoological garden in India and South Asia[14][15][16] and one of the largest in the world. Work started in 1979 at an initial cost of  75 million, and the zoo in its new premises was officially opened to public on 24 July 1985 by the then chief minister of Tamil Nadu M.G. Ramachandran, when most of the works were completed. In 2001, 92.45 hectares (228.4 acres) of land next to the park was acquired to build a rescue and rehabilitation center for confiscated and abandoned wild animals, increasing the park size to 602 hectares (1,490 acres).

The zoo was the first to hold an All-India Zoo Superintendents Conference in 1955, as part of the centenary celebrations.[17] The zoo is named after Tamil politician Arignar Anna. During April 2010-March 2011, the zoo attracted nearly 1,810,846 visitors against 11,87,904 visitors in 2006-2007.[18] In November 2010, the total revenue was  46.9 million against  40.2 million during October 2009.[19][20] There has been an increase of more than 200,000 visitors in 2010 compared to 2009 and the park had recorded a 21 percent increase in the number of visitors.[21][22][23] The number of visitors raises to the peak on the Kaanum Pongal day, a day in the festival season of mid-January, when the visitor count goes up to 35,000 in a single day.[24] An all-time record of 57,000 visitors a day was registered on the Kannum Pongal day of 2009, resulting in a revenue of  1.015 million.

The park is located at Vandalur in the southwestern part of the Chennai Metropolitan Area, about 6 kilometres (3.7 mi) from Tambaram and about 15 kilometres (9.3 mi) from Chennai Airport. The entrance to the zoo lies in the eastern side of the Chennai-Tiruchi Highway (National Highway 45), also known as the Grand Southern Trunk (GST) Road. Public buses from the park include A18 (to Broadway), B18 (to Korukkupettai), PP66 (to Poonamallee), PP70 (to Avadi), 114 (to Red Hills), 170A (to Madhavaram) and 170T (to Kaviarasu Kannadasan Nagar). Other buses which go to Guduvanchery, Chengalpet, Maraimalai Nagar, Mahendira City, Thiruporrur and Mamallapuram also stop at the zoo. There are 92 bus services to Vandalur every day of the week, and in addition to this, there are 90 bus routes that go via Vandalur to places like Guduvanchery and Chengelpet. The Chennai suburban railway network has a stop named "Vandalur" about 1 kilometre (0.62 mi) from the main entrance of the park.