Belem Tower is a historic fortress located in Lisbon, Portugal. Built in the early 16th century, it served as a defense system at the mouth of the Tagus River and as a ceremonial gateway to the city. The tower is a prime example of Manueline architecture, characterized by intricate stonework and maritime motifs. The structure stands about 30 meters tall and features a mix of defensive and decorative elements, including battlements and a beautiful balcony. Today, Belem Tower is a UNESCO World Heritage Site and a popular tourist attraction, reflecting Portugal's rich maritime history.