Teutonic Knights conquered the Ełk area in 1283. They built first a wooden castle to the site of former Old Prussian settlement and the town grew around it. It was first documented in 1398. The brick castle was built in 1497. In 1888 the castle was rebuilt - it became a prison and had that function until 1976. In 1958 during renovation of part of ther castle, under its walls, there was a collapsed tunnel found. After 1985 the castle doesn't have nor any function neither conservation care.
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.