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Road junction

In the field of road transport, a road junction is a place where two or more roads either meet or cross. The main types of road junctions are intersections and interchanges. A road junction may also be called a crossroads. A junction between 3 road segments (arms) is a T junction (two arms form one road) or a Y-junction.

Table of contents
1 Terminology
2 Intersections
3 Interchanges
4 Types of interchanges between two freeways
5 Types of interchanges between a freeway and a non-freeway road


Note: The descriptions of road junctions are for countries, like the United States, where vehicles drive on the right side of the road. For countries where they drive on the left, the junctions are the mirror image (the same except that right and left are reversed).

A ramp is a short section of road which allows vehicles to enter or exit a freeway (motorway).

Weaving is an undesirable situation in which traffic veering right and traffic veering left must cross paths within a limited distance. Weaving creates both safety and capacity problems.


An intersection is a road junction at which roads meet at grade. Types of intersections include:


A highway interchange is a road junction that utilizes grade separation, and one or more ramps, to permit traffic on at least one road to pass through the junction without crossing any other traffic stream. A complete interchange has enough ramps to provide access from any direction of any road in the junction to any direction of any other road in the junction. A complete interchange between two freeways requires 8 ramps. A complete interchange between a freeway and another road (not a freeway) requires 4 ramps.

Types of interchanges between two freeways

Types of interchanges between a freeway and a non-freeway road