The ancient ruins of the Colosseum can be visited in Italy, specifically in its capital, Rome. This iconic structure is a symbol of ancient Roman engineering and architecture, initially built for public spectacles such as gladiatorial contests. Completed in AD 80, the Colosseum could seat tens of thousands of spectators and features an intricate system of vaults and arches. Today, this UNESCO World Heritage site attracts millions of visitors annually, making it one of the most popular tourist destinations in the world, offering insights into Rome's rich history and cultural heritage.