Crossword Clue:

Natural boundary

Answer	Crossword Clue
RIVER	Natural boundary
URALS	Natural boundary between two continents.
URALS	Natural boundary between Europe and Asia.

LINE	Boundary
METE	Boundary.
EDGE	Boundary
LIMIT	Boundary.
SIDE	Boundary
METE	Boundary
MERE	Boundary.
PARAMETER	Boundary

BOURNE	Boundary
LINE	Boundary.
LIMITATION	Boundary.
LIMIT	Boundary
END	Boundary
END	Boundary.
AMBIT	Boundary
HEDGES	Boundary markers

LIM	Boundary: abbr.
ROPES	Ring boundary.
ATOLL	Lagoon's boundary
HEDGE	Bushy boundary
EDGES	Boundary lines
RIMROCK	Plateau's boundary
GUTTER	Lane boundary
EDGE	Outer boundary

METE	Boundary line
URALS	Europe-Asia boundary
STYX	Hades boundary
MEMBRANE	Cell boundary
RAIL	Track boundary
HORIZON	Earth-sky boundary
PERIMETER	Outer boundary
STYX	Boundary river

EDGE	Boundary line
QUARTILE	Statistical boundary
BORDER	Country's boundary
CURB	Block boundary
STAKE	Boundary marker