Carrowkeel is a cluster of passage tombs in south County Sligo, Ireland. They were built in the 4th millennium BC, during the Neolithic era. Nearby are the Caves of Kesh and Heapstown Cairn. The Carrowkeel tombs are protected National Monuments and are considered one of the 'big four' passage tomb cemeteries in Ireland, along with Carrowmore, Brú na Bóinne and Loughcrew.
The bones curated in Cambridge at the Leverhulme Centre for Human Evolutionary Studies were researched by the Human Population Dynamics at Carrowkeel Project. The original excavation mistakenly dated the monuments as Bronze Age structures, but the new study has shown that the sites were in use between c. 3,500 and 2,500 Cal. BC. Of 22 stable isotope samples, the majority indicated that the dead had grown up in a carboniferous limestone region, probably close to Carrowkeel. The DNA genomes assembled from six individuals indicated ancestral origins in Anatolia, and greater affinity with the Mediterranean than the Danubian expansion of early farming in Europe.
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.