The Stoa of Attalos was a covered walkway or portico in the Agora of Athens. It was built by and named after King Attalos II of Pergamon, who ruled between 159 BC and 138 BC. The current building was reconstructed in 1952–1956 by American architects along with the Greek architect Ioannis Travlos and the Greek Civil Engineer Yeoryios Biris.
Typical of the Hellenistic age, the stoa was more elaborate and larger than the earlier buildings of ancient Athens. The stoa's dimensions are 115 by 20 metres and it is made of Pentelic marble and limestone. The building skillfully makes use of different architectural orders. The Doric order was used for the exterior colonnade on the ground floor with Ionic for the interior colonnade. This combination had been used in stoas since the Classical period and was by Hellenistic times quite common. On the first floor of the building, the exterior colonnade was Ionic and the interior Pergamene. Each story had two aisles and twenty-one rooms lining the western wall. The rooms of both stories were lighted and vented through doorways and small windows located on the back wall. There were stairways leading up to the second story at each end of the stoa.
The stoa is identified as a gift to the city of Athens for the education that Attalos received there. A dedicatory inscription engraved on the architrave states that it was built by Attalos II, who was ruler of Pergamon from 159 BC to 138 BC.
The stoa was in frequent use until it was destroyed by the Heruli in 267. The ruins became part of a fortification wall, which made it easily seen in modern times. In 1952-1956, the stoa was fully reconstructed and the Ancient Agora Museum was created by the American School of Classical Studies at Athens, with funding donated by the Rockefeller family.
The Stoa of Attalos houses the Museum of the Ancient Agora. Its exhibits are mostly connected with the Athenian democracy. The collection of the museum includes clay, bronze and glass objects, sculptures, coins and inscriptions from the 7th to the 5th century BC, as well as pottery of the Byzantine period and the Turkish conquest.
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.