'''Surat''' is a port city and administrative headquarters of the Surat District. As of 2007, Surat and its metropolitan area had a population of approximately 4 million. It is the second largest city in Gujarat and ninth largest in India. Surat is a major gem stone center, and over '''92% of the world's diamonds''' are cut here. The city is located on the banks of the '''Tapti River''', and was a major port during the British colonial era. However, due to damming projects, the Tapti River become unnavigable and a new port was constructed down stream at the suburb of Hazira.The city is located at '''21.17° N 72.83° E.1 and is very low lying'''. The '''STD code''' of Surat is 0261-'''Climate''': The climate is tropical and the city receives the full impact of the monsoon.Winter Temperature: Max 31°C, Min 12°C Summer Temperature: Max 42°C, Min 24°C Rainfall: mid-June to mid-September 931.9 mmLowest Recorded Temperature: 6.5°C Highest Recorded Temperature: 48°C http://wikitravel.org/en/Surat