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We all know our way around a roundabout and everyone is familiar with a crossroads. But do you know the difference between the many types of multi-level interchange used on motorways and expressways, or why one might be chosen over another?

This page explores the different types of interchange you'll find all over the UK on limited access roads — roads with flyover junctions that separate fast moving traffic from the local road network.

Visitors to this page might also find the Dictionary helpful.

Motorway to road interchanges


Conventional, basic motorway-to-road connection.


Halfway between a diamond and a roundabout interchange.


A junction with no bridges and not much choice if you're on the side road.

Roundabout InterchangeRoundabout Interchange

The true British interchange.

Three-way interchanges


One way on and one way off: a fork in the road.


Three levels of road, three roads connected, three ways to build it.


The simplest free-flowing three-way connector.

Four-way interchanges


Four symmetrical loops — it's impossible to miss a cloverleaf. If you can find one, that is.

Four Level StackFour Level Stack

It is big, and it is clever.

Partially Unrolled CloverleafPartially Unrolled Cloverleaf

A clever improvement on the cloverleaf.

Three-Level Stacked RoundaboutThree-Level Stacked Roundabout

A cheap and cheerful way to fully grade separate two intersecting roads.


Free-flowing, resizeable and also quite pretty.

It looks like an octopus.