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Manson, Iowa: Largest Crater in the U.S.

Manson's annual celebration is called "Greater Crater Days" in honor of a much-studied yet invisible crater.

Hwy N65, Manson, IA
On Hwy N65 one mile north of its intersection with Hwy 7.
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Largest Crater in the United States

Barringer Crater in Arizona might be the most picture-worthy crater but in order to find the largest crater you have to travel to Manson, Iowa. Where Arizona's biggest crater measured only half a kilometer in diameter and left a 1.2 km diameter crater, Manson's meteorite was 2 km in diameter and left a whopping 38 km diameter crater! Only problem is a later ice age wore the crater smooth and filled it with rocks from far North, leaving the site as flat as a pancake.

Still, the crater is actually there and if you ask the good people at the local library they will show you articles and artifacts related to the crater.

[Greg Brown, 07/24/2007]
Great Crater - Meteorite Dinosaur Killer?

Manson lies near the center of a 24 mile wide crater that was created 74 million years ago when a meteorite crashed to earth. Researchers believed at one time that this meteorite caused the deaths of the dinosaurs. Manson's annual celebration is called "Greater Crater Days" in honor of the much-studied yet invisible crater.

[Ruth Rice, 04/12/2007]

We wouldn't detour too far for an invisible crater. Greater Crater Days is held in late June, though the event doesn't spend any time pondering prehistory. There's no Miss Teen Crater Pageant...

Nearby Offbeat Places

Pocahontas: the Princess GiantPocahontas: the Princess Giant, Pocahontas, IA - 15 mi.
Replica Cardiff GiantReplica Cardiff Giant, Fort Dodge, IA - 17 mi.
Floyd of Rosedale: Famous PigFloyd of Rosedale: Famous Pig, Fort Dodge, IA - 20 mi.
In the region:
Tallest Double-Track Railroad Bridge in America, Boone, IA - 43 mi.

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