District of Columbia is about 2.8 times smaller than Lake Tahoe.

Lake Tahoe is approximately 502 km² (194 sq mi), while District of Columbia is approximately 177 sq km, making District of Columbia 35.26% the size of Lake Tahoe.
Tip: This to-scale comparison of Lake Tahoe vs. District of Columbia uses the Mercator projection, which distorts the size of regions near the poles.
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