The Puducherry (Region) spread in an area of 294 Sq. Km. erstwhile French establishments of Puducherry.
The Puducherry District comprises Puducherry, Mahe and Yanam regions. Puducherry region, lies on the east-coast, and consists of 12 scattered areas lying in between 11o 42’ and 12o 30’ N, and between 76o 36’ and 79o 53’ E.
Semi-arid type of climate, with a mean annual temperature of around 30o C and 70-85 % relative humidity, is prevalent in the Union Territory. While Puducherry region receives rain mostly through North-East monsoon.
The region is flat country of average elevation of about 15 meters above sea level, intersected by the deltaic channels of River Gingee and Pennaiyar and other streams forming the two main drainage basins, interspersed with lakes and tanks. To the North-West of Puducherry town, a girdle of low hills (or an elevated ground of about 30 meters high) is noticed to extend in a East North East – West South West direction. This high ground suddenly emerges from the low alluvial plain country known as “Les Montagnes Rouges” or the “Red Hills of Puducherry”, or Gorimedu, probably so named after the memorials put up during the first siege of Puducherry (1760). This forms the most prominent feature in the landscape. River Gingee crosses the region diagonally from north-west to south-east. Pennaiyar forms the southern border. Actually the alluvial delta of Pennaiyar is almost on dead level ground, only a few meters above the sea. To the north-west of these hills is a section of fossiliferous limestone formations of the Cretacian age. To the south of this area is situated the alluvial tract of Varahanadi (Gingee) and to the north is the recent alluvium.
The population of Puducherry District(Census, 2011) is 9.50 lakhs. Women and men constitute exactly 50% of the population (4.82 lakh). The UT has registered significant reduction in population growth rate compared to the previous decade (1981-1991) which was 2.90%. Population growth rate in Puducherry is also impacted by migration from Tamil Nadu, Kerala and Andhra Pradesh. The projected population of the UT will be around 12 lakhs at present.