In the end, it came down to an educated guess as to which Bavarian city located on the Danube River was a legislative seat of the Holy Roman Empire from 1663 to 1806.
Answer: The German city of Regensburg.
And with that, 14-year-old Rahul Nagvekar took the top prize on Thursday at the National Geographic Bee.
It was a close victory. He and runner-up Vansh Jain had finished the championship round tied after five questions. Next, they were asked a series of tiebreakers in a sudden death round. For the first three, both wrote down the correct answer. On the fourth, only Nagvekar was correct.
"It was a guess, a 50-50 chance," said the eighth-grader from Sugar Land, Texas.
"It just happened to be a good guess."
The first-time contender in the national competition will receive a $25,000 college scholarship along with a trip to the Galapagos Islands. It was the third time a student from Texas has won the bee in the past four years.
Nagvekar's mother, Urmila Sabnis, said that helping her son train required her to do a lot of research with her husband.
"I have been reading and reading and reading ...just to be able to make it tough," said the software engineer who's originally from India. "He wouldn't take a question if it was easy."
Nagvekar said maps have fascinated him for years, but he's not sure what he'll study when he gets to college in a few years. He started preparing for the geography bee in fourth grade and has gone to the state bee every year, placing higher each time.
This year's bee began with local competitions among 4 million students in schools across the country.
"I think it's very important for people to know more about the world," Nagvekar said. "That helps with world conflict. It helps people understand others better. It helps people understand why problems happen and how to solve those problems."
The bee tested the 10 finalists' knowledge of history, world cultures, landmarks and climates.
In one round, students were shown a graph with rainfall and temperature averages and asked to pick which city it depicted. Another round used Google Earth to zoom in on a museum, memorial or church, and the students guessed where it was located.
President Barack Obama asked a question this year by video, quizzing the young contenders on their knowledge of recent events. Obama asked what Asian capital city on the Han River hosted a gathering of world leaders in March for a Nuclear Security Summit.
The answer: Seoul.
Obama said studying geography is "about more than just memorizing places on a map.
"It's about understanding the complexity of our world, appreciating the diversity of cultures that exist across continents, and, in the end, it's about using all that knowledge to help bridge divides and bring people together."
The contest will be televised on Thursday night on the National Geographic Channel and later on public broadcast stations.
Jeopardy! host Alex Trebek hosted the finals.
National Geographic changed the format this year. Rather than eliminate finalists after two wrong answers, the finalists earned points for each correct answer. During four elimination stages, those with the lowest scores were culled.
Jain, a 13-year-old from Minocqua, Wisconsin, will take home a $15,000 scholarship as runner-up. The eighth-grader was making his third appearance in the national geography bee.
"You have to love to look at maps," he said. In his spare time, he also is on the swimming team and plays the flute in his school band.
The third-place finisher, 13-year-old Varun Mahadevan of Fremont, California, wins a $10,000 scholarship.
Fifty-four contestants representing each state and four US territories competed in Washington. The 10 who made the final rounds represented Arizona, California, Louisiana, Maryland, Massachusetts, Minnesota, New Hampshire, Texas, Utah and Wisconsin.
Brian McClendon, vice president of engineering at bee sponsor Google, said it is the nation's best academic competition. Still, it's often overshadowed by the National Spelling Bee.
"You 50 or 54 are the smartest people I know," he told the contenders.