Niederkastenholz castle is surrounded by a moat, with an angular main castle and a separate horse-shoe shaped fore-castle with working quarters. It used to belong to Kornelimünster Abbey. The rough stone buildings of the castle are complemented by the wrought-iron gate. The fortified tower dates back to the 12th century and is the oldest part of the castle.
The so-called Probstei was added onto the medieval main castle between 1752 and 1756. Part of the moat is still visible today, although most of it was filled in during the 19th century.
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The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.