The best known ancient Greek pyramid is known as the Pyramid of Hellinikon . In the time of the geographer Pausanias it was considered to be a tomb.
The age of this structure is a matter of some controversy as various dating methodologies have provided conflicting results. But the most likely estimate is that it was built some time in the 4th century BC. However some archaeologists have argued that it dates as far back as the third millennium BC which would mean its construction corresponded with those in Egypt. This would provide some support for the mythological links supposed to have existed between Egypt and Argos.
As with other Greek pyramids the size of the one at Elliniko is considerably smaller than those in Egypt; the external base is just 7 metres by 9 metres. Another difference is that it did not have a pointed top. The walls slope at an angle of 60 degrees for 3.5 metres after which there was a flat surface. Internally there is a narrow corridor leading off the entrance at the South East side of the pyramid. This corridor provides access to the main interior room which is around 7 metres square.
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.