At the foot of the Monument to the Discoveries is a giant marble wind rose embedded in the pavement.
A map of the world at the center of the wind rose charts the Portuguese explorations.
The map shows the most important dates in the history of the discoveries, and ships mark the locations where Portuguese explorers first set foot on land.

I was only able to capture partial of the map (Europe & Africa), since a big group of tourists were standing on "the rest of the world".