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Jefferson County

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Also known as Jefferson County, Montana, Jefferson County, MT

county in Montana, United States

Key facts

Country
United States
State
Montana
Founded
February 2, 1865
Named after
Thomas Jefferson
Seat
Boulder
Largest town
Clancy
Total
1,659 sq mi (4,300 km )
Land
1,656 sq mi (4,290 km )
Water
2.6 sq mi (6.7 km ) 0.2%
Estimate 2025
13,329
Density
7/sq mi (2.7/km )
Time zone
UTC−7 ( Mountain )
Summer dst
UTC−6 ( MDT )
Congressional district
2nd
Website
www .jeffersoncounty-mt .gov

via Wikipedia infobox

~5 min read

Encyclopedic overview

Jefferson County is a county in Montana, United States. As of the 2020 census, the population was 12,085. Its county seat is Boulder. The county was created in 1865 and named for President Thomas Jefferson.

Jefferson County is part of the Helena, MT Micropolitan Statistical Area.

Excerpted from Wikipedia’s “Jefferson County” article, available under the CC BY-SA 4.0 licence.

On the map