Belem Tower
Lisbon, Portugal
A UNESCO World Heritage site, the iconic fortified tower (part of a defence system at the mouth of the Tagus river) was built in the early 16th century in the late Gothic Manueline style. It was said to be the last thing Portuguese explorers saw when departing as well as the first thing they saw upon return. It was later used as a prison for political prisoners, and is today one of the most recognized symbols of Lisbon and Portugal.