Controlled-access highway
A
controlled-access highway is a highway designed for high-speed vehicular traffic, with all traffic flow and ingress/egress regulated. Common English terms are
freeway and
motorway. Terms in other languages include
Autobahn,
autostrada,
autopista,
autosnelweg and
autoroute. It can be referred to less precisely as
highway or with more precise terms such as
expressway,
Interstate, or
parkway. They may also be called
limited-access highways, although this term can also refer to a class of highway with somewhat less isolation from other traffic. A controlled-access highway provides an unhindered flow of traffic, with no traffic signals, intersections or property access. They are free of any at-grade crossings with other roads, railways, or pedestrian paths, which are instead carried by overpasses and underpasses across the highway. Entrance and exit to the highway are provided at interchanges by slip roads, which allow for speed changes between the highway and arterial roads and collector roads.