Klusenstein castle was built in 1353 by Gerhard of Plettenberg, a vassal of earl Engelbrecht III of the Mark. The castle formed the boundary fortification of the earldom Mark to the bishopric state of Cologne and the earldom Arnsberg. All three territories met at the Hönne river valley, the castle was also overlooking an old road crossing the valley. During the feud between earl Engelbert and Gottfried IV of Arnsberg, the castle was under siege in 1366, but did not fall.
When the last earl of Arnsberg, Gottfried IV, sold the earldom to the bishop of Cologne, the castle lost its importance. Until the 17th century the family of Werminghausen owned the castle. During the 30 years war (1618-48) both Swedish and Hessian troops stayed in the castle. In 1695 the Brabeck family bought the castle, and was sold in 1812 to the Löbbecke family. In 1904 it was sold to the Hoesch company, and now belongs to the company Rheinkalk.
The castle is located on a 60m high cliff over the Hönne river valley, at around the narrowest part of the valley. At the bottom of the rock is a small cave in total 51m long. One corridor bends upward, but about 30m below the plateau it is blocked by stones. There were legends about a secret escapeway of the castle, in 2003 the top entrance to the cave was found below the eastern palais destroyed in 1840.
Below the castle is a mill, however though named Klusenstein mill it did not belong to castle. Since 1912 the railway connecting Balve and Menden runs directly below the castle.
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.