South India is the India that the north doesn't quite prepare you for — older temples, a different light, languages that share no cognate with Hindi, and a culinary tradition so sophisticated it has been shaping the diet of Southeast Asia for a thousand years.
The Dravidian temple is the defining architectural gesture of the south, and nothing else in India quite replicates the feeling of standing beneath a gopuram — those soaring, densely carved gateway towers that can rise twelve stories above a Tamil Nadu town. Madurai's Meenakshi temple has been in continuous religious use for two thousand years. Thanjavur's Brihadeeswarar, built by the Chola king Rajaraja I around 1010 AD, remains so structurally astonishing that historians still argue about how the builders raised the 80-tonne capstone to the top of the 66-metre tower without mechanised equipment.
Kerala is the specific answer to the traveller who says they've already done India and found it overwhelming. The backwaters move at the pace of a houseboat poled by a single man. Ayurvedic medicine, genuinely practised here rather than packaged for tourist brochures, has its most sophisticated lineage in the vaidya families who have been passing down texts and formulations for generations. The food — coconut-rich curries, fish baked in banana leaves, the extraordinary seafood of the coastal towns — is arguably the most immediately satisfying regional cuisine in the country.
Karnataka keeps the south's best-kept secret: Hampi, the ruined capital of the Vijayanagara Empire, which at its 14th-century peak was among the largest and wealthiest cities on earth. Today it is a landscape of surreal beauty — enormous rounded boulders scattered across red earth with carved temple complexes and market streets emerging from between them. The Coorg highlands, with their coffee estates and Kodava culture, are the south's other discovery: a territory of remarkable food, remarkable biodiversity, and a people whose identity has resisted absorption with admirable tenacity.