Commerce Square, also known as Praça do Comércio, is one of the most iconic and grand public spaces in Lisbon, Portugal. It is located near the Tagus River and is known for its stunning architecture, including the Arco da Rua Augusta, and its historical significance as the former site of the royal palace until it was destroyed by the great earthquake in 1755. The square is now a vibrant area with restaurants, shops, and cultural events.