natural boundary
River or mountain
A natural boundary is a geographic feature—river, mountain range, ocean, or desert—that forms a border between territories.
Unlike political boundaries drawn by treaty, natural boundaries follow the landscape: The Rhine served as a natural boundary between ancient Gaul and Germania.
The term also extends to any inherent limit or division: There's no natural boundary between species in the fossil record.
- species barrierLimit on interbreeding
- forest edgeBoundary of wooded area
- mountain rangeSeries of connected peaks
- wetlandWaterlogged land ecosystem
- riverLarge flowing watercourse
coastline · sea cliff · coral reef · cell membrane · strait · land bridge · timberline · valley · glacier · ice shelf · canyon · ecological niche · buffer zone · no man's land · desert · alpine region · mangrove swamp · plateau
- variational calculusnecessary conditions, geodesic, geodesics, catenary, critical point
- bordersborder, border crossing, national borders, international borders, border markers
- boundariesborders, border, edges, edge, limits
- ecoregionsecoregion, boreal forest, bioregion, biome, arctic zone
natural boundaryfence
Boundary structure between properties
wall · demarcation line · fortification · border wall · partition
natural boundarypolitical boundary
Edge of governmental jurisdiction
imaginary line · demarcation line · latitude line · meridian · property line
natural, boundary, nature, natures, naturals, naturally, naturalness, naturalize, naturalized