Fort Pannerden was constructed between 1869 and 1871 to serve as part of the New Dutch Waterline. Originally built completely out of brick and mortar, with just one main battery guarding the Rhine, it was upgraded significantly during 1885-1895. The main battery was completely rebuilt, with armour and concrete, while two additional armoured batteries were added and the roof of the fort was reinforced with concrete. The fort had strategic significance in that it guarded the Pannerden Canal, which supplied the water for the inundations of the New Dutch Waterline and could potentially be used as a route towards the main line of defence, but the fort saw little active service.
In World War I the Netherlands remained neutral, although the fort was manned as part of a general mobilisation. In World War II on May 10, 1940, during the German invasion of the Netherlands, the fort was first bypassed and then surrounded. On May 11, cut off from the rest of the Dutch army, the commander of the fort surrendered under threat of artillery bombardment and air attack. Most of the fort was subsequently stripped of all useful materials and after 1945 the building fell into disuse.
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.