I'd vote for Colorado. Beautiful scenery, challenging climbs. Lots of tourisim, so good options to ride from ski resort to ski resort, or small ski towns.
Another option is the Blueridge Parkway, Skyline Drive in the eastern part of the country.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.