A highway is a roadway for land-based non-track-guided vehicles, which has limited access to intersecting routes. In general it is only possible to enter and leave a highway from major thoroughfares or widely spaced roads; driveway turnoffs are generally not possible. Exits and entrances are often via ramps, with crossovers at each intersection to maintain traffic flow.

The restriction concerns where traffic can enter and leave the route. Direct access to individual driveways is generally absent under the stated meaning.

Ramps and crossovers are common means of maintaining through traffic. Their usual presence does not make a particular ramp layout essential to the limited-access roadway form.