Al-Muallaq Mosque was built in 1758 by the Arab ruler of Acre, Zahir al-Umar. It was built in a courtyard on the site of a structure commissioned by the Crusaders and which later became the gate to the Genoaese quarter of the city. Up until 1746, the structure was used as a synagogue by Acre's Jewish residents, called the Ramchal Synagogue. The Jews still owned the building when Zahir chose to transform it into a mosque, but compensated them with a different building located in Acre's Jewish quarter. Leftover features of the synagogue include the niche for the Holy Ark and inscriptions in Hebrew.
The mosque is positioned along the edge of Acre's Old City market, situated between Khan al-Umdan and Khan al-Ifranj, and is risen over the street. From the outside, the main indicators of the mosque are its low-lying dome and the round base of its former minaret. The mosque's entrance is located beneath the original minaret's base. This minaret was demolished by the municipality of Acre in 1950, citing a public safety risk. The body of the mosque is mainly constituted by a large, square-shaped prayer hall, A triple-domed portico precedes the prayer hall's entrance. Beside the prayer hall is a smaller room that is currently used as a library. A stairway beneath a covered entryway leads into the courtyard.
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.