Coetan Arthur dolmen, also known as Arthur's Quoit (not to be confused with Carreg Coetan Arthur, near Newport) is the remains of a Neolithic burial chamber (also known as a quoit). It dates from around 3000 BCE. The site, situated on the hillside close to St Davids Head in Pembrokeshire, Wales, is the collapsed chamber of what is presumed to be a passage grave which also has a round barrow. The massive capstone measures approximately 6 metres by 2.5 metres and is supported on one side by an orthostat approximately 1.5 metres in height.
References:The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.