Rawa Mazowiecka Castle is a Gothic style square formation castle located in the lowlands of the river Rawka and the river Rylka. Currently it is a renovated ruin.
According to the scriptures of Jan Długosz, the castle was built by Casimir III the Great, and the stronghold's function was to protect the southern borders of Masovia. Although reconstruction efforts have been raised by Franciszek Lanckoroński, the reconstruction was stopped, most likely due to the Partitions of Poland, after which the Prussian authorities ordered to deconstruct the ruins, only keeping the tower. The rest of the brick material was used for nearby housing. Currently the renovated tower is open to tourists, and the outline of the castle's former square formation has been reconstructed around the tower.
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.