Karnataka is the state we send people to when they have done the north and assume they have seen India. It has the ruins, the palaces and the temples, but almost none of the crowds – Hampi on a January morning is a UNESCO World Heritage Site with more langurs than visitors.
It also has the best road-trip geography in the south: Bengaluru to Mysore to Coorg to the coast is a continuous descent from plateau to plantation to sea, and every leg is under five hours.