Fifty-five state and territorial champions went into Tuesday's elimination rounds, with the top ten advancing to the finals.
Bee rules allow each contestant to get one wrong answer before being eliminated on their second miss. Snaring was the only contestant to not miss a single question either day.
"It [has] taken years, but there's a girl up here," Trebek said as he called Snaring to the stage to receive her award.
Each of the top three finishers had competed in the national finals before.
Ten of the 55 contestants had been state champions in previous years, and 7 of those 10 survived elimination and made it into Wednesday's championship round.
The three first-time state champions to reach the finals were Solomon Mayer of Kentucky, Tyler Bowen of Oklahoma, and Benjamin Taylor of West Virginia.
All three were eliminated in the fifth round of questions, leaving only the more experienced contestants to vie for the championship.
Andrew Lee of Alaska stumbled in round seven.
Lee's question: Burushaski, a language isolate—meaning that it is not related to any other known languages—is spoken in the Gilgit District of what country containing part of the Karakoram Range? (Answer: Pakistan.)
In round nine, remaining finalists were given a series of five place names. Four were related in some way, and contestants had to name the one that did not belong and also state why.
Colorado's Antonio de la Peña failed to single out Adelaide as a city in South Australia, listed among four other cities in Queensland state.
Arildsen missed noting that the Nubian Desert is in Africa. The four other deserts listed are in Asia.
And Puerto Rico's Francisco Vargas was eliminated by not naming the Cook Strait as the only one of the five straits mentioned not located in the Northern Hemisphere.
That left only Snaring and Iyer in contention for the championship. But first, a tense elimination round for third place was held among de la Peña, Arildsen, and Vargas.
After de la Peña faltered early, Arildsen and Vargas each answered a series of questions correctly.
Finally, Vargas faltered on the following question: The Ogaden is a dry, sparsely populated region that was fought over by Ethiopia and what bordering country in the 1970s? (Answer: Somalia.)
To claim the championship, Snaring finally wore down Iyer by answering all of her final questions correctly:
What is the Arabic term for a valley in the hot desert areas of northern Africa and the Middle East that carries a stream occasionally? (Answer: wadi.)
In late March 2007, Protestant and Catholic political leaders from Northern Ireland agreed to form a power-sharing government that took effect in early May 2007. The leaders met in what city that lies at the mouth of the Lagan River? (Answer: Belfast.)
The second largest oil producer in sub-Saharan Africa is also the richest Portuguese-speaking country in Africa. Name this country. (Answer: Angola.)
Lampedusa, an island whose geographical location has made it a target for illegal immigrants seeking to enter the European Union from Africa, is administered by which country? (Answer: Italy.)
A city that is divided by a river of the same name was the imperial capital of Vietnam for more than a century. Name this city, which is still an important cultural center. (Answer: Hue.)
Traci Snaring, Caitlins mother, said that after last year's competition, she asked her daughter if she really wanted to go through the pressure of competing again. But Caitlin had made up her mind.
"She took one day off after the bee last year, and then she started studying," Traci Snaring said.
Asked if she could explain the lack of girls among the bee finalists, Caitlin Snaring said she thought many were more attracted by spelling bees.
"For all you girls out there who like spelling," the champion said, "you might want to try geography, too."
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