I believe it was Bill Bryson who said that the mere visit of Stonehenge takes approximately eleven minutes. In that he is probably right.
Cleverly, the English Heritage has spiced it up a bit with a small preparatory museum, a couple of life-sized, paleolithic huts, a shuttle to take you to and from the rocks, the mandatory cafeteria and one of the most fanciful gift shops I have ever encountered.
The stones themselves were majestic and imposing, though I'd be hard pressed to say whether that is due to the formation itself or to everything you have heard and read about them. Not that I'm sure it really matters.