Underground expedition to a Mãe d'Água in Portuga where fresh water would go from a spring, down the hill inside this tunel, finally reaching the town. It was mostly dry but the beauty of that hardly hand-constructed tunel remains. We had to use our lanterns to light up the way and see what was right in front of us (such as some spider webs!). At the top, it finally ended with an amazing view of the city from above the mountain.