“Aha! Now I get it!”, we said it nearly at the same time. While cycling through South America, we were visiting historical sites from different civilizations in different countries. In Cartagena we visited one last place – San Felipe Fortress. We were sitting on the few hundred year old wall, looking at modern city and Atlantic Ocean in front of us and listening to the history on the audio guide. Suddenly, all the pieces from the puzzle came together. Silver mines in Potosi, origin of the name Argentina, cross-country tunnels in Ecuador – it all became one clear picture.