Eynhallow Church is probably the ruin of a 12th-century Benedicitne monastery. Because of the name of the isle it is likely that Eynhallow was an important religious centre. Eyin-Helha is Old Norse for Holy Isle.
Eynhallow Church was deserted before the reformation (circa 1560). The church was converted into dwellings in the 16th century. In 1851 the inhabitants of Eynhallow were transferred elsewhere and the church and other buildings were stripped of their roofs. The ruin was consolidated by W.R. Lethaby in 1897.
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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.