SizeGuess
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The measurement collection

Geography size comparison library

Compare the published lengths of lakes and other geographic features. The drawings are schematic icons, not map outlines; the specified length is what the game measures.

Play the geography game ↗Open the size comparison tool

6 objects

geography

Grand Canyon

446 kmlength

Published canyon length of 277 river miles, rounded to 446 km.

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geography

Lake Erie

388 kmlength

Published maximum length, rounded to 388 km.

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geography

Lake Huron

332 kmlength

Published maximum length, rounded to 332 km.

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geography

Lake Michigan

494 kmlength

Published maximum length, rounded to 494 km.

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geography

Lake Ontario

311 kmlength

Published maximum length, rounded to 311 km.

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geography

Lake Superior

563 kmlength

Maximum published length, 350 miles, rounded to 563 km.

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Get a sense of scale.

  1. Find your reference.The forest-green shape has a known measurement. Check the height, length or diameter label.
  2. Resize your guess.Use the slider, the − / + buttons, or drag sideways on the board. Arrow keys adjust the slider.
  3. Lock it in.The teal outline reveals the recorded true size. Earn up to 100 points per round; five rounds make 500.
Full rules & scoring

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