Australian Capital Territory is about 2.1 times smaller than Grand Canyon National Park.

Grand Canyon National Park is approximately 4,863 km² (1,878 sq mi), while Australian Capital Territory is approximately 2,358 km² (910 sq mi), making Australian Capital Territory 48.49% the size of Grand Canyon National Park.
Tip: This to-scale comparison of Grand Canyon National Park vs. Australian Capital Territory uses the Mercator projection, which distorts the size of regions near the poles.

Compare further: Australian Capital Territory vs. Grand Canyon National Park

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