London is about 2.3 times smaller than Long Island.

Long Island is approximately 3,566 km² (1,377 sq mi), while London (including the 32 boroughs of greater London) is approximately 1,572 sq km, making London 44.08% the size of Long Island.
Tip: This to-scale comparison of Long Island vs. London uses the Mercator projection, which distorts the size of regions near the poles.
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