The Papal Basilica of St. Paul outside the Walls (Basilica Papale di San Paolo fuori le Mura), is one of Rome's four ancient major basilicas. The Basilica was founded by the Roman Emperor Constantine I over the burial place of St. Paul, where it was said that, after the Apostle's execution, his followers erected a memorial, called a cella memoriae.
In 386, Emperor Theodosius I began erecting a much larger and more beautiful basilica with a nave and four aisles with a transept; the work including the mosaics was not completed until Leo I's pontificate (440–461). Under Pope St. Gregory the Great (590–604) the Basilica was extensively modified. The pavement was raised to place the altar directly over St. Paul's tomb. A confession permitted access to the Apostle's sepulcher.
As it lay outside the Aurelian Walls, the Basilica was damaged in the 9th century during a Saracen raid. Consequently, Pope John VIII (872–82) fortified the Basilica, the monastery, and the dwellings of the peasantry, forming the town of Joannispolis. It existed until 1348, when an earthquake totally destroyed it.
The graceful cloister of the monastery was erected between 1220 and 1241.
On 15 July 1823, a negligent workman repairing the lead of the roof, started a fire that led to the near total destruction of this basilica, which, alone among all the churches of Rome, had preserved its primitive character for 1435 years. It was re-opened in 1840, and reconsecrated in 1855 with the presence of Pope Pius IX and fifty cardinals. The complete decoration and reconstruction, in charge of Luigi Poletti, took longer, however, and many countries made their contributions. The Viceroy of Egypt sent pillars of alabaster, the Emperor of Russia the precious malachite and lapis lazuli of the tabernacle. The work on the principal façade, looking toward the Tiber, was completed by the Italian Government, which declared the church a national monument.
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.