London is about 1.5 times smaller than Australian Capital Territory.

Australian Capital Territory is approximately 2,358 km² (910 sq mi), while London (including the 32 boroughs of greater London) is approximately 1,572 sq km, making London 66.67% the size of Australian Capital Territory.
Tip: This to-scale comparison of Australian Capital Territory vs. London uses the Mercator projection, which distorts the size of regions near the poles.
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