Two states are neighbors when they share a border. Knowing neighbors helps you find states and understand how people, rivers and roads cross from one state to the next.
Key idea
Neighboring states share a border along a line. Tennessee and Missouri each touch eight states, the most of any. Maine touches only one: New Hampshire. Alaska and Hawaii touch no other state.
Why it works
Why does Tennessee have so many neighbors? It is long and thin, stretching all the way from the Appalachians to the Mississippi River, so its edges run past many states. A long border on many sides means many neighbors. Maine sits in a corner with Canada on two sides and the ocean on the third, so only one state is left to touch.
Worked example: Count Colorado's neighbors
How many states share a border with Colorado?
- North: Wyoming and Nebraska.
- East: Kansas and the tip of Oklahoma.
- South: New Mexico.
- West: Utah.
- Arizona touches Colorado only at a point, so it does not count.
Answer: 6 states.
Common mistake
At the Four Corners, Utah, Colorado, Arizona and New Mexico meet at one point. Arizona and Colorado touch only at that point, and so do Utah and New Mexico. A single point is not a shared border, so those pairs are not neighbors. Also, in this course a border means land: Michigan meets Minnesota only out in Lake Superior, so they are not counted as neighbors.