Vehicles are allowed to enter and leave an expressway only at designated locations.
There are no intersections, so cross-traffic is eliminated and traffic flows in only two directions.
Expressways include freeways, interstates and toll roads.
Traffic usually moves at higher speeds. To keep the flow of traffic smooth, expressways have maximum and minimum speed limits. Also to prevent slow traffic and for everyone's safety, pedestrians and bicyclists are not allowed on these roads. ome expressways are curved, banked and designed to maximize safety at higher speeds.
This type of roadway communicates with drivers through large directional signs. They are easy to read and placed in locations that give drivers plenty of time to maneuver if they need to get on or off the expressway. Usually, one-mile prior to each exit, at least three signs are posted to help drivers prepare to exit.
Watch for distance to exit and lane positions.
There are also "exit" signs to inform drivers where the exit is located.
Interchanges
Interchanges are designed to connect drivers to other expressways on smaller state highways, through a carefully developed system of ramps and over/underpasses.
This allows for fewer interruptions of the traffic flow.
Types of interchanges include designs that are shaped like a cloverleaf, a diamond and a trumpet. A cloverleaf interchange is designed to eliminate conflicting traffic when you make a left turn or try to cross traffic. diamond interchange is used when a road with low traffic intersects an expressway.
Left turns can be made with lower risk on the low traffic road, so a full cloverleaf is not necessary or economical.
Trumpet interchanges are used when a low traffic road ends at a t-intersection of an expressway.
The trumpet shape allows traffic to enter and leave the expressway without having to cross traffic.