The basic tale of how Stonehenge came to be bought at auction by local barrister Cecil Chubb in 1915 is fairly well known. He reportedly went to the sale looking for some chairs (or perhaps curtains, or maybe a present for his wife Mary - the stories vary) and bought Stonehenge on a whim for £6,600.
In his own words:
“...while I was in the room I thought a Salisbury man ought to buy it and that is how it was done.”
The full saga is somewhat more complex.