Flathead Lake is around the same size as Antigua and Barbuda.

Antigua and Barbuda is approximately 443 sq km, while Flathead Lake is approximately 510 km² (197 sq mi), making Flathead Lake 15% larger than Antigua and Barbuda.
Tip: This to-scale comparison of Antigua and Barbuda vs. Flathead Lake uses the Mercator projection, which distorts the size of regions near the poles.
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