Thanks for your question.
You can check who owns the land by submitting an index map search to the Land Registry, download Form SIM from the Registry's website and send it with a map of the area edged red. They will tell you the registered title number of the property so that you can get office copy entries to tell you who the registered proprietor is or if the land is un registered.
In order to claim possession of the land you must 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.
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 property of the land would be free to object and make representations as to why you should not have legal title of it though.
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