Martha's Vineyard is around the same size as Lake of the Ozarks.

Lake of the Ozarks is approximately 212 km² (82 sq mi), while Martha's Vineyard is approximately 227 km² (87 sq mi), making Martha's Vineyard 7% larger than Lake of the Ozarks.
Tip: This to-scale comparison of Lake of the Ozarks vs. Martha's Vineyard uses the Mercator projection, which distorts the size of regions near the poles.
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