Belém Tower on the bank of the Tagus River, Lisbon, Portugal

Belém Tower, Lisbon, Portugal

Ships leaving Lisbon once passed a small stone tower before meeting the wide Atlantic. That tower, standing on the bank of the Tagus River, served as both a guardian and a farewell. Say hello to Belém Tower—a fortress that watched Portugal sail into the Age of Exploration.

Built in the early 1500s under King Manuel I of Portugal, the tower helped defend Lisbon's harbour while explorers set out to chart new sea routes. Its Manueline design mixes Gothic forms with maritime symbols—stone ropes, shields and sea-inspired carvings that clearly embraced their oceanic purpose.

The tower once stood on a small island, but shifting riverbanks brought it closer to land. Inside were cannons, soldiers and even prisoners. Today, this UNESCO World Heritage Site is proof that some landmarks truly stand the test of time and tide.