WASHINGTON (AP) _ A Montana youngster who knew that the Tagus River divides Portugal into two agricultural regions won the sixth annual national geography bee today and a $25,000 scholarship from the National Geographic Society.

Anders Knospe, 14, of Bozeman, Mont., bested a field of 10 finalists to win the championship. Michael Bebow, 14, of Metairie, La., guessed incorrectly that the Tagus divides Italy and fell to second place. He received a $15,000 scholarship.

Third place went to Jeorse Lund, 14, of Henderson, Nev. He was ousted when he couldn't come up with the Dutch word for land reclaimed by the sea. (It's ''polder.'') His prize: a $10,000 scholarship.

The 10 finalists, all between 11 and 14 years old, breezed through the early rounds of the bee, which was moderated by Alex Trebeck, host of the TV game show ''Jeopardy.''

A total of six million students participated in the bee, which began at schools around the country in December. Fifty-seven state-level winners - representing the states, U.S. territories and overseas dependents - competed for today's 10 finalist slots.

Today's winners will travel to London this summer to compete in National Geographic's second international geography bee.

Knospe, an eighth-grader at Chief Joseph Middle School, said he was ''very happy'' the competition was over. While he said he was not as nervous today as he was at the state championship, he almost got the last question wrong.

''I thought it was Spain,'' he said.