The U.S. Congress has mandated funding for six parkways:
- The Chickamauga-Chattanooga National Military Park Bypass
- The Baltimore-Washington Parkway
- The Cumberland Gap National Historic Park Tunnel
- The George Washington Memorial Parkway
- The Natchez Trace Parkway
- The Foothills Parkway
These parkways offer exceptional travel experiences for Americans and foreign visitors. For example, the parkway portion of the Natchez Trace Parkway, completed in 2006 after 67 years of construction in Tennessee, Alabama, and Mississippi, is now considered one of the most scenic and beautifully designed parkways in America, and is designated as an "All American Road" scenic byway.
Four out of the six congressionally mandated parkways have been completed. The Natchez Trace Parkway is complete with the exception of a multi-use trail, and the Foothills Parkway's is complete with the exception of a series of bridge structures.