History of Estonia between 1800 BC - 501 BC
The beginning of the Bronze Age in Estonia is dated to approximately 1800 BC. The development of the borders between the Finnic peoples and the Balts was under way. The first fortified settlements, Asva and Ridala on the island of Saaremaa and Iru in the Northern Estonia began to be built. The development of shipbuilding facilitated the spread of bronze. Changes took place in burial customs, a new type of burial ground spread from Germanic to Estonian areas, stone cist graves and cremation burials became increasingly common aside a small number of boat-shaped stone graves.
About 7th century BC, a big meteorite hit Saaremaa island and created the Kaali craters. About 325 BC, the Greek explorer Pytheas possibly visited Estonia. The Thule island he described has been identified as Saaremaa by Lennart Meri, though this identification is not widely considered probable, as Saaremaa lies far south of the Arctic Circle.
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.