The Tower of Hercules

The Tower of Hercules (Torre de Hércules, or Farum Brigantium) is the only ancient Roman lighthouse still in operation.
This incredibly robust structure, located in the north-western Spanish city of La Coruña, has given rise to a series of myths related to its origin.
According to the most shared one, the divine hero Hercules after defeating his opponent, the giant Geryon, decided to bury his head and weapons and then ordered to build a city on the same field.

We can find a representation of this story in the coat of arms of the city of La Coruña which clearly shows the giant's skull and crossbones buried under the same tower.