Donegal Castle was the stronghold of the O'Donnell clan, Lords of Tír Conaill and one of the most powerful Gaelic families in Ireland from the 5th to the 16th centuries. For most of the last two centuries, the majority of the buildings lay in ruins but the castle was almost fully restored in the early 1990s. It is now open to the public.
The castle consists of a 15th-century rectangular keep with a later Jacobean style wing. There is a small gatehouse at its entrance mirroring the design of the keep. The complex is sited on a bend in the River Eske, near the mouth of Donegal Bay, and is surrounded by a 17th-century boundary wall. Most of the stonework was constructed from locally sourced limestone with some sandstone.
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.