There are 23 counties in the U.S. state of Wyoming. First there were five counties in the Wyoming Territory. They were Laramie and Carter, formed in 1867; Carbon and Albany formed in 1868; and Uinta, an added portion of Utah and Idaho, extending from Montana (including Yellowstone Park) to the Wyoming-Utah boundary.[1] On July 10, 1890, Wyoming was admitted to the Union with thirteen counties.[1]
The Federal Information Processing Standard (FIPS) code, used by the United States government to uniquely identify states and counties, is provided with each entry.[2] Wyoming's code is 56. When combined with any county code it would be written as 56XXX. The FIPS code for each county links to census data for that county.[3]