Once you've crossed the bridge, the old quarter rewards a slow wander. The Plaça de la Llibertat is the main square — the social and commercial heart of the town, surrounded by arcaded buildings and a good place to get your bearings. From there, everything is within a few minutes' walk.
Look for the Casa Cornellà, a fine Romanesque house on the main street with a well-preserved façade that shows what prosperous medieval domestic architecture looked like. The ruins of the Sant Julià i Santa Basilissa church, partially standing beside the old walls, add another layer to the town's medieval depth.
The Call — the old Jewish quarter — occupies a compact area of lanes near the mikveh. The community that lived here was one of the most important in medieval Catalonia; walking the narrow streets with that in mind gives them a different weight.