This 18th-century Baroque chapel was built over a hermitic Visigoth grotto on the Douro riverbanks. It is located on the Machado Route and inside you can see impressive frescos that narrate the life of San Saturio, a hermit from a noble 5th-century family that was canonised when he donated all his goods to the poor and went to live as an anchorite in this grotto where you can find his tomb and remains.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.