Inishmurray may be named after the early saint, Muiredach mac Echdach (fl. early 6th century) of Killala. There are remains of an early Irish monastic settlement. Laisrén (Saint Molaise) Mac Decláin reputedly founded a monastery here in the 6th century. He was confessor of Saint Columba (Colmcille) after the Battle of Cúl Dreimhne on the mainland nearby.
The island's ecclesiastical settlement was attacked in 795 and again in 807 by the Vikings, and eventually the monks abandoned the island and it remained uninhabited until the first secular settlement, probably in the 12th century.
The enclosure wall is impressive - reaching 4.5 metres in height at its highest point and up to 3 metres thick. The site contains various ecclesiastical buildings including enclosures, a stone-roofed oratory, two churches, a clochán, a large beehive-shaped cell, a holy well and other remains including cross slabs suggesting foreign influences. The whole complex is composed of what is probably local sandstone rubble.
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.