natural boundary
Any nonartificial thing (such as a river or ocean) that forms a boundary of a nation, a political subdivision, or a piece of property. — Also termed natural object. [Cases: Boundaries 4. C.J.S. Boundaries §§ 5–6.]
Any nonartificial thing (such as a river or ocean) that forms a boundary of a nation, a political subdivision, or a piece of property. — Also termed natural object. [Cases: Boundaries 4. C.J.S. Boundaries §§ 5–6.]