As the first eclipse to pass over the lower 48 US states since 1918, the event is being billed as the "Great American Total Solar Eclipse." It won't technically be be visible from every US state, but the eclipse will follow a diagonal path from northern Oregon, over Kansas, Missouri and Tennessee in the nation's center and head back out to sea through South Carolina. According to Space.com, that puts over 220 million people within a one-day drive of the totality zone -- directly passing over 12 states and catching the edge of an additional two.
Even if you do make the trek out, the phenomenon won't last long -- at best, the full eclipse will only last two minutes and forty seconds. Still, if you're looking for an excuse to plan a road trip next year, a once-in-a-lifetime solar eclipse is a pretty good one.