FIGURE 4.32 The Tower of Belem in Lisbon, Portugal. In order to protect the wealth brought by his growing empire in Asia, Africa, and the Americas, King Manuel I of Portugal constructed a system of defense around the capital of Lisbon. Built from 1513–1519, during an era of great prosperity, the Tower of Belem was both a central part of this defense and a ceremonial gateway to and from the city. For many of the Portuguese expeditions of discovery and colonization, including most of the colonization of Brazil, the tower of Belem was the last architectural symbol of home the travelers saw as they left on their long voyages. Courtesy Mauricio Abreu/AWL Images/Getty Images