The Porto Cathedral, also known as Sé do Porto, is a magnificent Romanesque-style cathedral that dates back to the 12th century. It is one of the oldest and most important religious buildings in Porto. The cathedral features stunning architectural details, including its rose window, Gothic cloister, and beautiful azulejo tiles. Visitors can explore the interior of the cathedral, climb the bell tower for panoramic views of the city, and visit the nearby archaeological site.