Moralha Fernandina is a series of walls built around the city of Porto for protection, dating back to the thirteenth or fourteenth century, and tells the story of the city of Porto and its development over time from a small city to a large city as it is now, and the walls can be seen from several directions, the best of which is located on the side The other side of the Douro River, it offers a wonderful sight worth spending a few minutes observing.