There was a famous case a few years ago of an old tramp ( can't think of another word off-hand) who'd built a shanty in the corner of a very large garden in London. The house owner wasn't bothered about him being there and then after maybe 15 or 20 years he gained ownership of the corner he'd built a fence around. Value somewhere near £1 million or something horrendous. He wasn't interested in selling, just being left alone.
Happens all the time, most commonly it is houses and it is property developers benefiting.
Put simply, if you take possession of land and use it at the exclusion of all others, you may have a claim to that land.
It's an ancient law, and an important one, it allows the recycling of land and houses that have fallen out of use and have no obvious owner.
Look at derelict properties, there are three in my road alone. Many will simply decay without the law allowing for their recycling through adverse possession laws.
