The coconut groves which appear as one approaches Pondicherry conjure a picture of idyllic beauty. Bounded by Bay of Bengal on the east with a coastal length of about five mile, the town stands only a few feet sea level, in the alluvial delta of the Ponnaiyar, interspersed with numerous lagoons, of which the Grand Etang or Lake Ousteri is the largest.
The river skirts parts of the southern border of the state. The Gingee or Varahandi River crosses it diagonally from the north-west to the south –east, running 34 km in the state. At a distance of seven kilometersw from its mouth, it branches into two, the southern branch known as Chunam or Kilinjar and the northern, really a lagoon, knows as the Ariankuppam river fringed by coconut palms. This, known today as Arikamedu, is the site of the buried Produke which traded with the Greco-Roman world in the early centuries of the Christian era. The excavations of 1945 have unearthed Arretine (red-glazed Italian) ware, and jars or emphorae with internal incrustations of Roma wire. To the west, 20 km from the town, is Tiruvakkarai, a wonderland of fossils, a section of the fossilifer4ous limestone formation of Cretacean age.
The Pondicherry state includes the far- flung and scattered areas of Karaikal, Mahe and Yaman, which were earlier also under French occupation. The density of the population in Pondicherry area is quite high, being 982 per sq km as compared with 316 sq in Tamil Nadu.