St. Ruprecht’s (Rupert’s) church is the oldest church in Vienna. It stands high up on the eastern edge of the old Roman military settlement. It is said to have been built by Bishop Virgil of Salzburg on the site of the subterranean Oratory of Cunard and Gisalrich, two apostles of the faith. The church is first mentioned in documents in 1161. There is evidence that the nave and the lower floors of the tower were built in the 11th c. the tower was twice made higher, in the 12th and 13th c. a choir was added in the 13th c., as was a south side aisle in the 15th c. the church was thoroughly restored between 1934 and 1936 and between 1946 and 1948. Its treasures include the oldest stained glass Vienna (13th c.) in the central windows in the choir, and the Altar of Our Lady of Loretto, the so called “Black Madonna”, whose aid was invoked when there was danger from the Turks or the plague.