Austrått Fort is a disused coastal artillery site constructed in 1942 by the German Wehrmacht to protect the Trondheimsfjord during the German occupation of Norway during World War II. The fort's centrepiece is a triple 28 cm SK C/34 naval gun turret from the German battleship Gneisenau, which was damaged in Kiel. The three gun turret weighs 800 tonnes and was capable of firing 38 kilometres. The last firing took place in 1953 and the fort was decommissioned in 1968. It opened as a museum in 1991.
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.