I found these pics at the North West 4x4 site.
http://www.northwest4x4.co.uk/
There at The Southport Leisure Lakes just north of Southport Merseyside.
I have been once.
It was a small but very muddy site with alot of soft sand too.
You WILL get stuck.
From the pics it looks like they have opened up more of the site and there is a huge amount of land around the site.
This place is on a caravan and camp site , with a bar.
The site was used by quads and bikes when I went.
Thje only othing as I mentioned at that time is was a small site.
Maybe its time for another recci
Ste