Dattenberg Castle was built around 1220 by the lower nobility Lords of Dattenberg as their ancestral seat. Around 1320, Wilhelm de Dadenberg sold the castle to the Archbishopric of Cologne, who granted it as a fief to the knight Rollmann von Sinzig in 1331 on behalf of Altenahr. Rollmann's grandson and his descendants bore the name von Dattenberg. Through Elisabeth von Dattenberg, wife of Goddart von Lülsdorf, the castle passed to her son Albrecht von Lülsdorf, who was granted possession in 1572. When Albrecht's successor, Ludwig von Lülsdorf, died without male heirs in 1664, his son-in-law, Johann Friedrich Raitz von Frentz zu Gustorf, received the fief in 1667, but it was confiscated as lapsed after his death in 1675. In 1624, the castle was already described as ruined.
Owned by the Prussian state, the castle was sold to Cologne's Appellate Court Councilor Dahmen in 1822. It then came into the possession of Josef Stoppenbach, a notary in Cologne, in 1837. Stoppenbach built a two-story country house with a tower-like staircase and farm buildings using rubble stones. The most significant construction work was carried out in 1840, but Stoppenbach went bankrupt in 1848, and his property was auctioned off in 1850. Otto von Mengershausen took over Burg Dattenberg until he handed over ownership to Berlin architect Adolf Fuchs in 1887, who then converted it into a villa resembling a castle in 1890. Adolf Fuchs cultivated vineyards and orchards in Dattenberg. From 1929 to 1938, his descendants had to rent out the property to Father Rudolf Schütz, who wanted to train young girls of all social classes according to the principles of the Catholic Laity Apostolate through his institution 'Heim in der Sonne.' In 1939, the Nazi state established a Landjahrlager on the premises, sometimes for boys and sometimes for girls. At the end of World War II, German soldiers entrenched themselves on the castle grounds until they were occupied by the Americans. After the property came into the possession of the District of Cologne in 1949, it was used as a rural boarding school by the Erft District until 1996 and became privately owned by Karin and Karl Schultz in 2003.
The former high castle complex consisted of a circular main castle, a rectangular enclosure wall, and a flanking tower at the northeastern corner. Today, it still shows the approximately 11-meter-high stump of the centrally located keep (residential tower) with a diameter of 8.5 meters, as well as a moat carved into the slate rock. The forecourt has been rebuilt in modern times. The most impressive part of the partially restored fortification is the ruin of the keep, which can only be viewed from the outside.
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.