Thanks Allens.
No such thing as 'public land' as such in England & Wales (is there anywhere these days?) and camping without permission from the landowner is officially illegal. However, in some National Parks a blind eye is turned if it is done responsibly ie leave no trace and NO fires (we had a very long dry summer last year and The Peak District was particularly vulnerable).
Everywhere else is a bit more edgy, and you run the risk of getting caught. All adds to the 'stealth' naughtiness of it though...
Scotland has a law where wild camping is fine as long as you are not causing landowners any trouble. As ever, they have a much more progressive outlook north of the border 8)
I just uploaded a new vid a couple of hours ago about a camp in The Peak District on Friday actually:
https://midlifecrisisbyvespa.blogspot.com/2019/03/my-dream-tent-clean-vespa-and-another.html