Desmo Paul wrote

Can a legal easement be obtained over land owned by a railway
company? Or rather could it be obtained say in 1955 whether latterly
repealed or not? It seems railway land was curiously protected?

So are urban commons !

There was a legal case in May/June 2007 which held (for Wimbledon
Common) that since the trustees had no power to grant an easement it
could not be acquired by adverse possession (squatters rights) either.

--
Mike D