Wrong-way multiplex

A wrong-way multiplex occurs when two or more roads become one physical road and two routes are signed in opposite directions. For example, Interstate 93 is multiplexed with Massachusetts State Highway 128 near Boston, but I-93 northbound is signed as going the same direction as MA-128 southbound and vice versa. At the multiplex of Interstate 77 and Interstate 81 in Virginia, I-77 northbound is signed as I-81 southbound and vice versa.

See also multiplex.