Spend the day exploring Madikeri Fort, Abbey Falls, and Raja's Seat, take a coffee plantation tour or go trekking in the hills.
Visit the Edakkal Caves and trek to Chembra Peak or Meenmutty Falls.
Explore the Thrissur Zoo, Vadakkumnathan Temple, and Athirapally Falls.
Take a houseboat ride through the backwaters of Alleppey, relax at the beach or visit the Krishnapuram Palace.
Watch the sunrise or sunset at the southernmost tip of India, explore the Vivekananda Rock Memorial and Thiruvalluvar Statue.
Visit the Ramanathaswamy Temple, Dhanushkodi Beach, and Pamban Bridge.
Explore Marina Beach, Fort St. George and Kapaleeswarar Temple in Chennai.
If you have more time, consider spending extra days in each location to more fully explore nearby attractions. If you have less time, skip the houseboat ride in Alleppey and spend more time in other locations.