City-Data.com has put together a list of the Top 10 Largest American Cities by Land. Check out the list below.
1

Alaska (2874.0 sq. mi.)
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2

Alaska (2716.7 sq. mi.)
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3

Alaska (1697.2 sq. mi.)
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4

Florida (757.7 sq. mi.)
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5

Montana (737.0 sq. mi.)
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6

Montana (716.1 sq. mi.)
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7

Alaska (684.8 sq. mi.)
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8

Alaska (669.0 sq. mi.)
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9

Texas (579.4 sq. mi.)
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10

Houston is the largest city in the state of Texas and the fourth-largest in the United States
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