The Giant's Ring is a henge monument at Ballynahatty, near Shaw's Bridge, Belfast. It dates from the Neolithic period and was built around 2700 BCE. It is near the Shaw's Bridge crossing of the River Lagan, a point which has been used as a crossing of the river since at least the Stone Age. The original purpose of the monument was most likely as a meeting place or as a memorial to the dead.
The site consists of a circular enclosure, 180 m in diameter and 2.8 hectares in area, surrounded by a circular earthwork bank 3.5m high. At least three of the five irregularly spaced gaps in the bank are intentional and possibly original. East of the centre of the enclosure is a small passage tomb with a vestigial passage facing west. There were reports of other tombs outside the enclosure, but there is no trace of these.
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.