Fodor's Expert Review Amphitheater

The sheer size of Trier's oldest Roman structure (circa AD 100) is impressive; in its heyday it seated 20,000 spectators. You can climb down to the cellars beneath the arena—animals were kept in cells here before being unleashed to do battle with gladiators. Gladiatorial performances (1¼ hours) take place Friday through Sunday and holidays at 6 pm from April through October. Tickets can be booked in advance at Tourist Information.