Tarragona was Tarraco, the capital of Roman Hispania Tarraconensis, and a city where Augustus and Hadrian both spent extended periods. The Roman remains are extensive, well preserved, and inscribed together on the UNESCO World Heritage list as the Archaeological Ensemble of Tárraco: the seafront amphitheatre, the chariot-racing circus, two forums, the city walls, the Pont del Diable aqueduct, and the necropolis at the Tower of the Scipios.
The old town that grew up among the ruins is also worth time — a tight knot of narrow streets between the cathedral and the medieval walls, with a Jewish quarter, several handsome squares, and a Modernista boulevard (the Rambla Nova) running along the cliff above the sea.