Which Is More Mountainous: Eastern or Northern North America?

Eastern North America is significantly more mountainous than northern North America.

Eastern North America

Features major mountain systems:

• Appalachian Mountains: Extend ~2,000 km from Alabama to Newfoundland—ancient, eroded, but prominent.
• Laurentian Mountains (Canadian Shield): Rugged, ancient terrain across eastern Canada.
• White Mountains, Green Mountains, Adirondacks, Catskills: Notable sub-ranges in New England and New York.

Northern North America (Arctic/Subarctic)

Dominantly flat to gently rolling:

• Canadian Shield: Vast, low-relief plateau of Precambrian rock.
• Arctic Coastal Plain: Flat, tundra-covered lowlands.
• Islands of the Arctic Archipelago: Mostly low-lying, with isolated mountains (e.g., Baffin Island).

Note: The Rocky Mountains and Sierra Nevada are in western North America, not eastern. The original answer incorrectly placed them in the east.