Avebury

Think of it like this: Stonehenge, but bigger, older, closer, and way less crowded.  Avebury is the largest existing stone circle in the world!  And you can actually walk among the stones along with the local sheep (the circle was originally SO big that you probably can't walk around it all) and touch them all you want.  The tiny village nestled in the area is also unbelievably charming.

Stones to build the henge were dragged to the site from great distances - even Wales- before the invention of the wheel! The story of how these stone circles were built is seriously mind-boggling, and there are a lot of mysteries that will remain unsolved.

Avebury has a handful of nearby sites that are equally amazing, including an earthen pyramid the size of the great pyramids that is still a complete mystery -- make sure to see them all.  Seriously awesome.

Recommended Reading: 

more about Avebury's history, here.