10 Years: The 1,900-mile Transcontinental Railroad (four of those years
during the Civil War).
12 Years: The 3,400-mile Lincoln Highway (the first U.S. transcontinental road).*
8 Years: Getting man to the moon.
20 Years: The 300-mile Interstate 11 (estimate in the Review-Journal, and that may not count construction time).
* “Let’s build it before we’re too old to enjoy it!” said Lincoln Highway founding father Carl G. Fisher.