natural barrier
Mountain or river
A natural barrier is a geographic feature that impedes movement or separates regions—mountains, rivers, deserts, oceans.
The Pyrenees form a natural barrier between France and Spain.
The term extends to anything inherent that blocks access or progress: Language can be a natural barrier to immigration.
- canyonsDeep, narrow valleys
- dense forestsClosely packed woodland areas
- dense vegetationClosely packed plant growth
- hedgeBoundary of planted shrubs
- cliffsSteep natural rock walls
deserts · boundary · wetlands · coral reefs · island chain · ravine · straits · mountains · glaciers · oceans · ocean current · rivers · river crossing · body of water · escarpment · temperature extremes · windbreak · floodplains
- defensibilitymoat, fortress, bunker, stronghold, citadel
- strategic locationschokepoint, strait, mountain pass, isthmus, bridgehead
- Ancient BordersHadrian's Wall, Great Wall, limes, defensive wall, Chinese wall
natural barrierfence
Boundary structure between properties
wall · dam · fortification · levee · seawall
natural barriernatural passage
Earth-made route through land
natural corridor · mountain pass · navigable waterway · land bridge · isthmus