Which US State Borders the Most Other States?

Geography questions about US state borders are among the most popular quiz topics — and one of the trickiest. Which state has the most neighbors? Which states share the longest border? Here's everything you need to know.

The Most Connected States

Tennessee borders 8 states: Kentucky, Virginia, North Carolina, Georgia, Alabama, Mississippi, Arkansas, and Missouri. Its elongated shape and central location in the South make it a geography crossroads.

Missouri also borders 8 states: Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas, and Nebraska. Missouri is the only state besides Tennessee to border 8 others.

Together, Tennessee and Missouri hold the record — no other US state has more than 8 neighbors.

The States With 6-7 Neighbors

Several states are close behind: Colorado borders 7 states (Wyoming, Nebraska, Kansas, Oklahoma, New Mexico, Utah, and Arizona). Kentucky borders 7 as well (Missouri, Illinois, Indiana, Ohio, West Virginia, Virginia, Tennessee). New Mexico also has 5 states plus two international borders if you count Mexico and the Texas panhandle properly.

The Most Isolated States

Maine borders only one other US state — New Hampshire. On the other sides are Canada and the Atlantic Ocean, giving Maine the most distinctly isolated position of any contiguous US state.

Hawaii borders zero US states — it's completely surrounded by the Pacific Ocean.

Alaska borders zero US states as well and is separated from Washington State by Canada.

The Longest US State Borders

The longest shared state border is between Nevada and California at approximately 420 miles. The longest international border shared by a US state is Alaska-Canada, which runs about 1,538 miles. Among contiguous states, the Oklahoma-Texas border along the Red River is one of the most distinctly shaped — Oklahoma has a "panhandle" that extends 166 miles west, creating a long, thin strip of land bordered by Texas to the south.

The Four Corners

The only point in the US where four states meet is the Four Corners Monument, where Colorado, Utah, Arizona, and New Mexico share a single point. You can technically stand in four states at once there.

Border Trivia

- The Kansas City metro area spans Kansas and Missouri — one city, two states, two time zones in some neighborhoods.
- Bristol, Virginia/Tennessee is a single city split down the main street by a state line.
- The Mason-Dixon Line (the Pennsylvania-Maryland border) was historically the dividing line between "North" and "South" and remains one of the most culturally significant state borders.
- The US-Canada border is 5,525 miles long, making it the longest international border in the world. Several US states (Maine, New York, Vermont, Michigan, Minnesota, Montana, Idaho, Washington, Alaska) touch Canada.

Understanding state borders is one of the most useful geography skills for quiz competitions and map-based challenges. Start with Tennessee and Missouri's 8 borders each, and you'll have the hardest question covered.