Flathead Lake is about 1.4 times bigger than Gaza Strip.

Gaza Strip is approximately 365 km² (141 sq mi), while Flathead Lake is approximately 510 km² (197 sq mi), making Flathead Lake 40% larger than Gaza Strip.
Tip: This to-scale comparison of Gaza Strip vs. Flathead Lake uses the Mercator projection, which distorts the size of regions near the poles.
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