Wrong-way concurrency
- 'WWM' redirects here. This may also refer to the TV documentary, Walking with Monsters.
A wrong-way concurrency is a road concurrency in which at least two numbered highway routes are signed in opposite, conflicting directions on the same stretch of physical roadway.
Although each route is logically consistent with itself, wrong-way concurrency signage may lead to confusion among motorists.
The road itself is likely to be actually pointed in a third direction. For example, a north-south wrong-way concurrency would typically occur on a stretch of road that physically runs east-west; and vice versa.
This oddity is not to be confused with situations where a north-south route shares an east-west route, which is a very common occurrence. Also, there are some cases where a route's posted direction is not the same for the entire route (thus need careful consideration of apparent wrong-way concurrency), with these examples:
- "Beltway" situation, such as I-695 around Baltimore and I-495 around Washington, DC.
- I-69, connecting Indianapolis and Port Huron, MI; south of Lansing, Michigan it is posted as north-south and east of Lansing it is posted as east-west.
- At least part of US 1 in Connecticut has been posted as east-west, although for the rest of its route (from Canada to Key West, Florida) it is posted north-south.