Praça do Comércio is a magnificent, highly accessible waterfront square in Lisbon, easily reached by metro (Terreiro do Paço station), tram, or foot, with flat terrain suitable for all visitors. It can be explored independently for free, enjoying its grandeur and riverside views, though guided city tours often include it for historical context. The square is open year-round with no seasonal restrictions, though spring and autumn offer the most pleasant weather, avoiding summer heat and peak crowds. While visiting the square itself is free, optional activities like ascending the Arco da Rua Augusta or dining at nearby establishments incur costs. A typical visit duration ranges from 30 minutes for a brief stroll to 1-2 hours if exploring the arch or simply enjoying the vibrant atmosphere, offering stunning photo opportunities and a central historical experience.