The Castle of Nice was a citadel used for military purposes. Built at the top of a hill, it stood overlooking the bay of Nice from the 11th century to the 18th century. It was besieged several times, especially in 1543 and in 1691, before it was taken by French troops in 1705 and finally destroyed in 1706 by command of Louis XIV.
Nowadays, Castle Hill is used as a park. It's the most famous public garden in Nice, and a 'must see' place for the numerous tourists who visit the city. It offers many amazing panoramas, and provides a beautiful view all day long from sunrise to sundown, highlighting various landscapes depending on where one looks: the Harbor at sunrise, the Promenade des Anglais at sundown. That's why Castle Hill is called 'the cradle of the sun'.
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.