The Great Cairn in Barnenez
The stone structure in Barnenez is the largest tombstone in Europe. This building, almost 75 meters long, 28 meters wide and over 8 meters high, was built between 4700 and 3900 BC. It hides 11 burial chambers and consists of two structures that differ in age: the older building (primary cairn) supports the later burial chambers, forming the so-called secondary cairn. Due to the time of its creation, it is also probably the oldest preserved building in the world (it was built about 2100 before the oldest, ie the Djoser Pyramid). It is estimated that 13-14,000 tons of stone from a kilometer distant quarry were used for the construction.