Erm, Jean Jeanie... I think you've perhaps got your sites mixed up. There definitely *is* a wall. You'll remember from your visit it's the one *right next to* the site!!! As seen in my photograph, here:

http://www.themodernantiquarian.com/image.php?image_id=3692

And again, quite clearly, in Fitz' shot:

http://www.themodernantiquarian.com/image.php?image_id=5018

I still don't understand how you got there if you didn't use the B6265, even if you were on a bike.

As for the pen system. There are three gates - one into one field, another for the track and finally one into the other field. They are gates *not* a pen system. There is a pen inside the field you have to cross, but it's not gonna get obstructed by a car parked on the verge away from the gates.

Moth - I had the same problem, by the way. The wall isn't on the map but is on the ground, as you said. Cross the wall and follow it up and you'll find the circle.