The Belem Tower, also known as the Tower of St. Vincent, is a 16th-century fortress located in Lisbon, Portugal. It was built as a symbol of Portugal's power and influence during the Age of Discovery and served as a lighthouse, defense tower, and customs checkpoint. The tower is considered a major tourist attraction and is one of Lisbon's most iconic landmarks. The Belem Tower is a UNESCO World Heritage Site, and its design incorporates elements of the Gothic and Manueline architectural styles, reflecting Portugal's wealth and influence during the Age of Exploration. The tower is open to the public for visits, and visitors can climb to the top for panoramic views of the river and city.