Penhallam is the site of a fortified manor house near Jacobstow in Cornwall. There was probably an earlier, 11th-century ringwork castle on the site, constructed by Tryold or his son, Richard fitz Turold in the years after the Norman invasion of 1066. Their descendants, in particular Andrew de Cardinham, created a substantial, sophisticated manor house at Penhallam between the 1180s and 1234, building a quadrangle of ranges facing onto an internal courtyard, surrounded by a moat and external buildings. The Cardinhams may have used the manor house for hunting expeditions in their nearby deer park.
By the 14th century, the Cardinham male line had died out and the house was occupied by tenants. The surrounding manor was broken up and the house itself fell into decay and robbed for its stone. Archaeological investigations between 1968 and 1973 uncovered its foundations, unaltered since the medieval period, and the site is now managed by English Heritage and open to visitors.
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.