In Memphis, I-40 was originally intended to go through the city's Overton Park toward downtown. Several miles of interstate were actually built within the I-240 loop; this portion of highway still exists and is in regular use. However, public opposition, combined with a court victory by opponents of the Overton Park route, forced abandonment of the plans, and the road never reached the park. For several years, I-40 signage existed on the dead-end route toward Overton Park. Eventually, the northern portion of the I-240 loop was redesignated as I-40.
The Government of California has submitted Highway 58 between Barstow and Bakersfield for I-40 extension potential.
Future Interstate 840 around Nashville, Tennessee was once planned to completely surround the city. But in October2003, Tennessee DOT discontinued plans for a northern loop around the city. Currently the Highway is signed as Tennessee 840.
I-40 in New Mexico has driveway entrances, contrary to standards, due to the extremely remote area I-40 passes through, making ramps much too costly for just ranch access.
