Annadorn dolmen has a large, low, slightly displaced capstone about 65 cm thick covering a rectangular chamber and supported by three stones about 60 cm high. An account of 1802 suggests that it was formerly set beneath a large rectangular cairn 60 ft in diameter and approached by a lintelled passage, so it could be the remains of a passage grave.
Another possible explanation could be that the supporting stones were originally upright supporting the capstone, representing a more typical tripod dolmen. The monument has not been excavated and closer examination would be required to correctly interpret the site. The capstone has many small solution pits on the upper surface, two of which appear to have been enlarged. The 1802 account also says the chamber under the capstone contained ashes and a number of bones.
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.