Laguna's historic centre covers the original colonial settlement on a promontory between the Atlantic and the Lagoa Santo Antônio. More than 600 buildings are protected as national heritage, and the overall streetscape — of low whitewashed houses, cobbled lanes, and Portuguese-baroque churches — is remarkably coherent. The main square, Praça Vidal Ramos, is flanked by the 18th-century Igreja Matriz de Santo Antônio and the old town hall from whose balcony the short-lived Juliana Republic declared independence in 1839.
The waterfront is the most atmospheric part of the historic centre, with fishing boats moored alongside the remnants of the colonial quay. The smell of fish is pervasive and genuine — Laguna is a working town, not a tourist recreation. The market near the harbour sells fresh catch in the mornings, and several simple restaurants along the front serve the same fish within hours of it being landed.