Thanks for your question.
There is nothing to stop you fencing it off, save for that if the Council asks you to unfence it you will have to do so.
If you wish to attempt to register the strip as your own then you would have to prove 'adverse possession" to the Land Registry.
If the land in question is unregistered then you must have been using it continuously for 12 years in order to claim possession of it and be registered as the registered proprietor at the Land Registry
If the land is registered then you need only have been using it continuously for 10 years in order to apply for adverse possession at the Land Registry. Notice of the application will be sent to the current registered proprietor of the land, who is obviously at liberty to object. It is therefore more difficult to claim adverse possession of land that is registered.
If you do not know whether the land is registered then you can check using the Land Registry's online service by downloading a copy of the register of the title (if any) for the property:-
If this does not illicit results then you should send a index map search to the Land Registry by using Form SIM (enclosing a map of the area), they will then tell you definitively if it is registered. You can also download that form from the LR website.
In the case of both applications you would have to submit form ADV1 to the Land Registry together with sworn statutory declarations regarding how long you have been using the land (from you and others who know of your use) and it may be something over which you should consider taking specific legal advice from a local solicitor to ensure that the application and supporting documentation is drafted correctly.
The Council could object and, if they do, you would be caught in a bit of a fight with them over it.
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