Annadorn dolmen has a large, low, slightly displaced capstone about 65 cm thick covering a rectangular chamber and supported by three stones about 60 cm high. An account of 1802 suggests that it was formerly set beneath a large rectangular cairn 60 ft in diameter and approached by a lintelled passage, so it could be the remains of a passage grave.
Another possible explanation could be that the supporting stones were originally upright supporting the capstone, representing a more typical tripod dolmen. The monument has not been excavated and closer examination would be required to correctly interpret the site. The capstone has many small solution pits on the upper surface, two of which appear to have been enlarged. The 1802 account also says the chamber under the capstone contained ashes and a number of bones.
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.