Hartashen Megalithic Avenue is a prehistoric megalithic monument in Armenia. There are two avenues of megalithic rocks which do not intersect. These avenues are composed of basalt stones which are placed at an angle, and menhirs are arranged in three rows in each. There is no clarity about the purpose of these three rows of menhirs and further research is under progress. There is no firm dating of the monument. It has been attributed in recent years to anti tank defences constructed in the Second World War, but recent research favours an interpretation that the site, if not its arrangement, dates to the neolithic or bronze age and perhaps shares a context with the Carnac stones of France.

The monument comprises 760 preserved steles. Some steles have been disturbed, and it is estimated there may have been up to 1200 originally. The flat surface between the monuments comprises an unexcavated funerary monument. No connection has been discovered between the avenue and the funerary monuments. The rows of stele begin at a rocky outcrop and follow the valley topography for 500 metres. The monument is not astronomically aligned, nor aligned with any features within the topography.

The arrangement of the stone rows were integrated into a modern anti tank military barrier. As there is no firm dating, it is unknown to what extent and in what form the avenues predate this modern use.