Every line on the U.S. map tells a great story: California's border was bent to claw onto lucrative gold deposits...Oklahoma's panhandle reflects a shifting national barometer for legal slavery...Kentucy, Tennessee and Virginia's shared border traces the scar of a meteor impact. The segments reveal the larger story of what makes America unique: a range of natural resources, a history of social experimentation, and a thriving democracy.

Based on the book by Mark Stein.