The original Roman Agora was encroached upon and obstructed by a series of Roman buildings, beginning with the imperial family's gift to the Athenians of a large odeion (concert hall). The Odeon of Agrippa was built by him in around 15 BC, and measured 51.4 by 43.2 metres, rose several stories in height, and – being sited just north of the Middle Stoa – obstructed the old agora. In return for the odeion, the Athenians built a statue to Agrippa at the site of the previous agora; they based it on a plinth recycled from an earlier statue by covering the old inscription with a new one.
After the invasion of the Herulae in AD 267 the city of Athens was restricted to the area within the Late Roman fortification wall, and the administrative and commercial centre of the city was transferred from the Ancient Agora to the Roman Agora and the Library of Hadrian.
During the Byzantine period and the Turkish occupation the area was covered with houses, workshops and churches along with the Fethiye Mosque.
The Tower of the Winds is an octagonal Pentelic marble clocktower that functioned as a horologion or 'timepiece'. It is considered the world's first meteorological station. The structure features a combination of sundials, a water clock, and a wind vane. It was supposedly built by Andronicus of Cyrrhus around 50 BC, but according to other sources, might have been constructed in the 2nd century BC before the rest of the forum.
The Gate of Athena Archegetis is considered to be the second most prominent remain in the site after the Tower of the Winds. Constructed in 11 BCE by donations from Julius Caesar and Augustus, the gate was made of 4 Doric columns and a base of Pentelic marble. It was a monument dedicated by the Athenians to their patroness Athena Archegetis.
The East Propylon is the eastern entrance of the Roman Agora in Athens. Built in 19-11 BCE, it constituted of 4 Ionic columns made of gray Hymettian marble.References:
Easter Aquhorthies stone circle, located near Inverurie, is one of the best-preserved examples of a recumbent stone circle, and one of the few that still have their full complement of stones. It consists of a ring of nine stones, eight of which are grey granite and one red jasper. Two more grey granite stones flank a recumbent of red granite flecked with crystals and lines of quartz. The circle is particularly notable for its builders' use of polychromy in the stones, with the reddish ones situated on the SSW side and the grey ones opposite.
The placename Aquhorthies derives from a Scottish Gaelic word meaning 'field of prayer', and may indicate a 'long continuity of sanctity' between the Stone or Bronze Age circle builders and their much later Gaelic successors millennia later. The circle's surroundings were landscaped in the late 19th century, and it sits within a small fenced and walled enclosure. A stone dyke, known as a roundel, was built around the circle some time between 1847 and 1866–7.