Dogging seems to be pretty much nationwide with virtually every county apparently having a site according to various hook up websites.
The activity seems particularly popular in  London with one survey claiming that 12 of the 21 most popular sites were in the area. Probably because the London area is so densely populated

Neighbouring Kent also high on the list but people getting frisky al fresco is by no means restricted to the South East of England.

Car parks up north are not left out with many northerners regularly having sex outside...