claim a peace of land

I have been useing a peace of land ner me for 17 yeas now just putting some sheep and cutting the hedge of it as it ws not getting used , no one ever come to see me or ask me anything, any way the house that is next to it has just been sold as the people have passed, on the advert for selling the house it says no one owns it, how do i claim it as over the lst 17 years no one has even been to ask me about it

John - if you are looking to claim land then our PGs 4 and 5 explain the registration requirements - Land registration: Practice guides - GOV.UK
You can check if the land is registered or not by applying for a search of the index map - Get information about property and land: Search the index map - GOV.UK
And do seek legal advice/assistance as you need to meet the complex legal requirements before tackling the registration ones