Praça da República is the compact centre of São João da Pesqueira, with the town hall, old civic buildings, and the slow rhythm of a small Douro municipality. It is not a grand square, but it is the right place to begin walking the town.
Use it as a counterweight to the vineyard stops. The Douro here is not only quintas and river views; it is also inland towns that have looked after the wine country for centuries.