My youngest brother, an engineer like me and our father, sent us this link showing how a fellow from Michigan, Wally Wallington, single-handedly lifted a Stonehenge-sized pillar weighing 22,000 lbs. I visited Stonehenge in June and learned that, prior to erecting these really large pillars, earlier builders (2000 BC!) put up 80 bluestones, up to 4 tons apiece, that they mined 240 miles away in Wales. These were thought to have been moved magically by the sorcerer Merlin. More likely these were transported much of the distance by raft and overland on rollers as demonstrated by the Millennium project.
I thought the bluestones were the coolest of all that I saw at Stonehenge, but you must look beyond the larger sandstone pillars to see them and appreciate how much older they are. For more on their history, see the Secrets of the Preseli Bluestones by Dr. Colin R. Shearing.
Any sufficiently advanced technology is indistinguishable from magic. — Arthur C Clarke