Gutenfels Castle was built in 1220. It was used with Pfalzgrafenstein Castle in the middle of the Rhein and the fortified town of Kaub on the far side to provide an impenetrable toll zone for the Holy Roman Emperor until Prussia purchased the area (1866) and ended this toll in 1867.
This castle, primarily owned (since 1257) by the Falkenstein family, is one of the most important examples of the Hohenstaufen military and house construction style at the Rhine. Since 1277 it has been a castle of the Electorate of Palatinate. After an unsuccessful siege in 1504 by landgrave Wilhelm from Hessen, the castle was renamed Gutenfels (solid rock). Rebuilt between 1889 and 1892 it is now used as a hotel.
References: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.