Parcel of public land. An overworked bureaucrat probably shouldn't be selling those off cheaply, should they? Some private land is even subject to the right to roam*, so the public can still access it.
America bootstrapped its private property market. (No. Bad elephant.) All of her land was "first" public land (or royal land) and then granted to private persons.
All of it was home to people already here, who didn't claim ownership the way we think of private, or even public, property. Perhaps "stolen land" would be apt.
*https://en.wikipedia.org/wiki/Freedom_to_roam