Boskednan stone circle is a partially restored prehistoric stone circle near Boskednan, 6.4 kilometres northwest of the town of Penzance in Cornwall. The megalithic monument is traditionally known as the Nine Maidens or Nine Stones of Boskednan, although the original structure may have contained as many as 22 upright stones around its 69-metre perimeter.
The stone circle once probably consisted of 22 granite blocks, from which 10 still survive. Six stones stand upright, one sits half a metre out of the ground, the others remain lying in the soil. The stones are all about 1 m high, the highest measure approximately 2 m and stand to northern edge of the circle. The stone circle originally described a circle with a diameter of approximately 22 m. The stone circle may have belonged with the nearby barrow to an extensive cult district.
Stone circles such as that at Boskednan, were erected in the late Neolithic or in the early Bronze Age by representatives of a Megalithic culture.
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.