Stonehenge SHOCK: Archaeologists reveal huge slabs DID arrive over Salisbury Plain

The notion the Altar Stone came from Milford Haven had a profound influence on theories as to how the bluestones were transported to Stonehenge — with the idea being that the Altar Stone may have been collected en-route.

Many experts accordingly suggested that, from Milford Haven, the bluestones and the Altar Stone were shipped on rafts up the Bristol Channel, before travelling the final leg to Salisbury Plain over land.

The theory had proven so popular, in fact, that a number of attempts have been made since to re-enact the journey.

Recent studies, however, have called into question the original connection between the Altar Stone and the sandstone outcrops in South Wales and Pembrokeshire — and similarly challenge the notion the blocks travelled by sea from Milford Haven.

Some researchers have even concluded the bluestones originated from the northern flanks of the Preseli Hills — meaning that, to go via Milford Haven and the sea, they would first have to have been tortuously hauled all the way over the hills.