If Pondicherry seems familiar to you, it may be from the scenes in Life of Pi that was filmed in the city. Explore this outpost of colonial France with its French bread and quiet streets and cuisine before venturing deeper into Tamil Nadu.
Much of France's colonial presence was erased by the Raj, but Puducherry/Pondicherry retains a distinctive French quality right down to Baquettes and cheese. The French quarter is well maintained as you would expect from a UNESCO centre, but the surrounding rather rambling city with its streets sloped to Mecca is almost more charming.
A short stay in Pondicherry is an opportunity to slow down from the bustle of Chennai and experience a sense of the colonial India rather like Fort Cochin.
Pondicherry Museum, Jesuit Cathedral, Church of Our Lady of Angels, Botanical Gardens, the Government part and must visits. Deep sea fishing trips can be arranged.