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Understanding Great Circle Routes — Why Flights Curve on Maps

Blog › Math · 6 min read · Published 2026-03-01

Discover why airplane flight paths appear curved on flat maps.

What Is a Great Circle?

The largest circle on a sphere's surface. The shortest path between any two points always lies along a great circle.

Why Flights Look Curved

Mercator projection distorts great circles into curves. The path is actually the straightest possible line on the sphere.

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