Roskilde Abbey or Our Lady's Abbey was a monastery of nuns dedicated to Saint Mary the Virgin. It was founded in the early 12th century for Benedictine nuns, but in 1177 became part of the Cistercian reform movement.
It was chiefly known for the tomb of Saint Margrethe or Margaret of Ølsemagle or of Højelse (both names of places near Køge), who, although murdered by her husband, had been wrongly buried as a suicide on the beach at Køge. After miracles were declared to have happened round her grave, her remains were moved to the Abbey Church, the Vor Frue church, in 1176 by Absalon of Lund, Bishop of Roskilde, a kinsman of Margrethe; he arranged for the construction of a suitable shrine in the church, and transferred the nunnery to the Cistercians in the following year. Despite Absalon's best efforts, and also despite the local veneration, Margrethe was never formally canonised. The shrine was nevertheless later declared a place of pilgrimage by the Pope, and the nuns were allotted one third of the income generated by it. Despite all efforts, however, the center of the cultus remained the small chapel built near Margrethe's original grave on the beach.
The abbey was suppressed in 1536 during the Protestant Reformation in Denmark. Around 1600 the convent buildings and the eastern half of the church were demolished. Today the former abbey church has a beautiful furniture from the 17th century.
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.