A large piece of dressed Welsh bluestone, likely to have been part of the first monument at Stonehenge. The stone is here on display at the British Museum in their World of Stonehenge exhibition.
A dressed Welsh bluestone at the British Museum's World of Stonehenge exhibition — likely from the original monument. It traveled 240 miles from the Preseli Hills in Wales. Someone made that decision and followed through. © -JvL-, CC BY 2.0, via Wikimedia Commons

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