This summer I'm planning a bicycle trip from Manchester (UK) to Trieste (ITA). I don't have a lot of money to spend in hostels or campings, therefore I was thinking that wild camping would be a good idea. But after a quick look at the net I discovered that wild camping in UK, Belgium and Holland is forbidden and it can be punished with prison.
So, you have got a lot of questions there at once, let me address two of them I do know about.
In the Netherlands this has been possible for quite a while and was originally called paalkamperen (though it seems it has officially been renamed sometime in the past 2 years), however it must be noted that this is bound by a lot of rules. Most importantly every spot has a designated number of tents that are allowed (normally 3 small tents), if you arrive too late and they are taken you aren't allowed to camp there. Beyond that you aren't allowed to leave any trash, no loud music, 10 meters from the sign, no more than 72 hours, no campfires etc. etc. Either way, a list can be found here. All of this is in Dutch though, so good luck with Google Translate.
Inspired by the Dutch, Belgium has recently set up a similar iniative called Bivakzone. It seems the rules are somewhat similar, though once again all information is in Dutch. Differences seem to be that it's max for 48 hours and that you will find water pumps more often than in the Netherlands (do note this is not drinking water).
From what I have heard this is not allowed whatsoever in the UK, but if it is I would love to hear about it (still hope to go hiking in scotland some day).
Important to understand
These locations really aren't meant for tourists. Not in the sense of that you aren't allowed to stay there, but you should note that not only information online is only in Dutch, but if you arrive on these locations you will find all signs to be in Dutch only as well. All in all these locations are meant for 'locals' and as a tourist it's not going to be the best holiday experience ever (they can be hard to find, etc.).
Either way, this site might be worth checking out as well, although it's once again in Dutch it does give a good overview both of the Dutch and Belgium situation.
The already provided answer is correct about wild camping in the Netherlands and in Belgium.
However, when it comes to wild camping in the United Kingdom:
- It is legal in Scotland
- In England and in Wales you will need permission from the landowner in all areas except for Devon and Dartmoor, there it is also legal.
- In certain National Parks (like Lake District) there is a lot of toleration by the Park Authority, even when it's strictly speaking not legal. For a full overview I would recommend on of my articles: Wild camping in the UK: complete legal overview
Additionally, you can find information about wild camping in every European country in this article that I wrote recently: Wild camping in Europe: Complete overview.