Hindwell pallisaded enclosure (Powys) is 34 hectares. That's a fair old size. Of course if you add in the whole landscape including Bache Hill, Whimble, 4 stones, hmmm.

What defines the boundaries is often the horizon....and beyond :-)

Many stone rows are now being set up over a long period of time - individual stones being set up by small groups rather than a single grant installation.

The other one is also the Dorest Cursus, but again I'd suggest this did not have the largest number of people in attendance and had a multi phase construction.