Vlatades Monastery was founded by the brothers Dorotheus and Markus Vlatadon, who were students of Gregory Palamas, in the latter half of the fourteenth century. It was first mention in a letter by Patriarch Matthew dated in 1400 to Metropolitan Gabriel of Thessalonica.
In 1387, Thessalonica and the monastery were occupied for the first time by the Ottoman Turks. While the monastic community held together, the monastery properties were sequestrated as royal property and the main church was converted into a mosque with the frescoes of its interior plastered cover. During the Turkish occupation a unit of Turkish troops, commanded by a cavus, was billeted at the monastery giving rise to the name Cavus Monastir, still often popularly applied to the monastery.
During the latter part of the sixteenth and most of the seventeenth centuries the condition of the Monastery of Vlatadon and its dependencies deteriorated. While supported by a succession of Patriarchs of Constantinople, the monks of the Monastery of Vlatadon attempted to recover and restructure their dependencies in Thessalonica.
By the mid-twentieth century the monastery became a meeting place for scholars and academics of the city. In 1965, the Patriarchal Institute for Patristic Studies was established that has worked closely with the Aristotelean University of Thessalonica. In recent years the Monastery of the Vlatades has been further renovated and expanded.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.