Lazio is a region of central Italy overlooking the Tyrrhenian Sea. Its capital, Rome, is the capital of Italy and was the heart of the ancient Roman Empire. Among its iconic monuments is the Colosseum, an amphitheater that could accommodate thousands of spectators. On the coast, the ancient port of Ostia still preserves refined mosaics and a theater. Inland there are the wooded mountains of the Apennines, with nature reserves, lakes and stone villages.