Start your Tamil honeymoon exploring the UNESCO World Heritage site of Mahabalipuram. Visit the Shore Temple, an ancient 8th-century stone temple built on the Bay of Bengal, followed by a stroll through the Pancha Rathas, a group of monolithic rock-cut temples in various shapes. Take in the beautiful carvings at the Arjuna's Penance, and end the day with a romantic walk along the Mamallapuram Beach.
Escape the heat and head to the charming hill station of Ooty for some stunning scenery. Indulge in the Ooty toy train ride, a scenic journey through the Nilgiri mountains that promises fantastic views of the valleys and waterfalls. Spend the rest of the day visiting the beautifully landscaped Ooty Botanical Gardens and Doddabetta Peak, the highest point in the Nilgiri range, which offers breathtaking panoramic views of the surrounding lush hills.
If you have more time, consider exploring the historic city of Chennai and stop by the Government Museum and Kapaleeshwarar Temple. Alternatively, if you have less time, you can skip Ooty and opt for a day trip to the Kanchipuram Temples or the Vedanthangal Bird Sanctuary.