Chennai pronunciation formerly known as Madras pronunciation is the capital of the state of Tamil Nadu and is India's fourth largest metropolitan city. It is located on the Coromandel Coast of the Bay of Bengal. With an estimated population of 7.60 million (2006), the 368-year-old city is the 36th largest metropolitan area in the world.

The city is a large commercial and industrial centre, and is known for its cultural heritage and temple architecture. Chennai is the automobile capital of India, with a major percentage of the automobile industry having a base there and with a major portion of the nation's vehicles being produced there. Chennai is also referred to as the Detroit of South Asia.

The name Madras is derived from Madraspatnam, the site chosen by the British East India Company for a permanent settlement in 1639. Another small town, Chennapatnam, lay to the south of it. In due course the two towns were merged, and the term Madras was favoured by the British. However locals used to refer to it as Chennapatnam or Chennapuri. The word "Chennu" is a South-Central Dravidian word of Telugu origin, meaning "Beautiful" and therefore Chennapuri or Chennapatnam meant "Beautiful City". The city was renamed Chennai in August 1996 as the name Madras was perceived to be of Portuguese origin. (A number of other Indian cities have enacted similar name changes.) It is believed that the original Portuguese name is Madre de Sois, named after a Portuguese high authority who was one among the early settlers in 1500. There have been suggestions though that Chennai may not be a Tamil name while Madras may be of Tamil origin.

History
The region around Chennai has served as an important administrative, military, and economic centre dating back to the 1st century. It has been ruled by South Indian kingdoms, notably the Pallava, the Chola, the Pandya, and Vijaynagar empires. The town of Mylapore, now part of the metropolis, was once a major port of the Pallava kingdom.

When the Portuguese arrived in 1522, they built a port and named it São Tomé, after the Christian apostle St. Thomas, who is believed to have preached there between the years 52 and 70. The region then passed into the hands of the Dutch, who established themselves near Pulicat just north of the city in 1612.

The British regained control of the town in 1749 through the Treaty of Aix-la-Chapelle and subsequently fortified the base to withstand further attacks from the French and Hyder Ali, the Sultan of Mysore. By the late 18th century, the British had conquered most of the region around Tamil Nadu and the northern modern-day states of Andhra Pradesh and Karnataka to establish the Madras Presidency, whose capital was Madras.

Under British rule the city grew into a major urban centre and naval base. With the advent of railways in India in the late 19th century, it was connected to other important cities such as Mumbai (formerly known as Bombay) and Kolkata (formerly Calcutta), facilitating communication and trade with the hinterland. It was the only Indian city to be attacked by the Central Powers during World War I, when an oil depot was shelled by the German light cruiser SMS Emden. After independence in 1947, the city became the capital of Madras State, which was renamed Tamil Nadu in 1969.

From 1965 to 1967, Chennai was an important base for the Tamil agitation against the imposition of Hindi. Chennai had witnessed some political violence due to the ethnic conflict in Sri Lanka, after 33 people were killed by a bomb planted by the Tamil Eelam Army at the airport in 1984 and following the assassination of thirteen members of the Sri Lankan separatist group EPRLF, and two Indian civilians by the rival LTTE in 1991. Strong measures were taken and the city has not faced any major terrorist activity since then. The city was renamed Chennai in August 1996 as the name Madras was perceived to be of Portuguese origin.

In 2004 the Indian Ocean tsunami lashed the shores of Chennai, killing many and permanently altering the coastline.

Climate
Chennai lies on the thermal equator, and thus sees little variation in seasonal temperature. Its proximity to the sea gives it a hot and humid climate for most of the year. The highest temperatures are experienced in late May and early June and usually vary between 38 °C (100.4 °F) and 42 °C (107.6 °F) though it sometimes nearly touches 45 °C (113 °F) for a few days. Average daily temperature in Chennai during January is around 24 °C (75 °F), though the temperature rarely falls below 18 °C (64 °F). The lowest temperature recorded is 15.8 °C (60.4 °F) and highest 47.1 °C (111.4 °F).

The average annual rainfall is about 1,300 mm (47.2 inches). The city gets most of its seasonal rainfall from the north-east monsoon winds, from Mid October to Mid December. Cyclones in the Bay of Bengal sometimes hit the city


Culture
Chennai's culture reflects its diverse population. The city is known for its classical dance shows and Hindu temples. Every December, Chennai holds a five week-long Music Season, which has been described as one of the world's largest cultural events.[18] The Music Season encompasses performances (kutcheries) of traditional Carnatic music by hundreds of artists in and around the city.

Chennai is also known for the classical Indian dance, Bharatanatyam, which is also the official dance of Tamil Nadu. An important cultural centre for Bharatanatyam is Kalakshetra (Sanskrit for "place of the arts"), located on the beach in the south of the city.

Chennai has a vibrant theatre scene, with a large number of Tamil plays being performed. In general, Tamil theatre is divided into the sabha-oriented theatre which are parodies on political issues or trends supported by slapstick comedy and the non-sabha oriented theatre which include serious plays and historical plays. English theatre is also popular. School and college cultural festivals (locally called culfests) play an important role by providing platforms for the city's youth to indulge in art and culture. Also present is an established and growing culture of bands in western and other styles.

Chennai is the base for the large Tamil movie industry, dubbed Kollywood after the locality of Kodambakkam where most of the movie studios are located. The industry makes about 300 Tamil movies a year, and its film soundtracks dominate the music scene in the city.

Chennai celebrates a number of festivals. Pongal, celebrated in the month of January, is the most important festival of and is celebrated over a period of five days. Tamil New Year's day signifying the beginning of the Tamil Calendar usually falls on April 14 and is celebrated widely. Being a cosmopolitan city, almost all major religious festivals like Deepavali, Eid and Christmas are celebrated here.
 

Geography
Chennai is located at 13.04° N 80.17° E on the southeast coast of India and in the northeast corner of Tamil Nadu. It is located on a flat coastal plain known as the Eastern Coastal Plains. The city has an average elevation of 6 metres (20 feet), its highest point being 60 m (200 ft). Two rivers meander through Chennai, the Cooum River (or Koovam) in the central region and the Adyar River in the southern region. Both rivers are heavily polluted with effluents and trash from domestic and commercial sources. The Adyar, which is much less polluted than the Cooum, is de-silted and cleaned periodically by the state government. A protected estuary of the Adyar forms the natural habitat of several species of birds and animals. The Buckingham Canal, 4 km (3 miles) inland, travels parallel to the coast, linking the two rivers. The Otteri Nullah, an east-west stream runs through north Chennai and meets the Buckingham Canal at Basin Bridge.

The geology of Chennai comprises of mostly clay, shale and sandstone.[7] The city is classified into three regions based on geology, sandy areas, clayey areas and hard-rock areas. Sandy areas are found along the river banks and the coasts. Clayey regions cover most of the city. Hard rock areas are Guindy, Velachery, Adambakkam and a part of Saidapet.[8] In sandy areas such as Tiruvanmiyur, Adyar, Kottivakkam, Santhome, George Town and the rest of coastal Chennai, rainwater run-off percolates very quickly. In clayey and hard rock areas, rainwater percolates slowly, but it is held by the soil for a longer time. The city's clayey areas include T.Nagar, West Mambalam, Anna Nagar, Kolathur and Virugambakkam.
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