The old town of Tui climbs the hill from the riverfront to the cathedral, a network of narrow cobblestone streets lined with granite-faced houses and occasional Roman remains. The architecture is unmistakably Galician — grey stone, glassed-in balconies called galerías, overhanging upper floors — but the town's border position has given it a Portuguese quality too.
The main strollable area runs from the Praza do Concello (town hall square) up to the cathedral, then down through quieter residential streets to the Miño waterfront. The town is quiet out of season and lively on summer weekends when Portuguese day-trippers and pilgrims on the Camino converge on it. The small museums near the cathedral — one focused on local history, another on archaeological finds — are worth a quick visit.