102. 環状道路
環状道路は、都市、町、市街地の周囲または一部を囲む道路、あるいは連続した道路網です。地域内の交通を分散し、通過交通が混雑した中心街を避けられるよう設計されます。
環状道路が必ずしも高速道路や自動車専用道路とは限りません。高速道路、分離道路、一般道路、または複数の道路種別の組み合わせで構成されることがあります。そのため速度制限、進入規制、優先関係、車線規則は各区間と現地の交通標識・規則によって異なります。
What is a ring road?
A ring road is a road or connected route that runs around or partly around an urban area and helps distribute traffic between different destinations without requiring all traffic to pass through the centre.
Why are ring roads built?
Ring roads are commonly used to divert through traffic, connect major roads and provide access to different parts of a city. They can reduce the amount of traffic travelling through central streets.
Is a ring road always a complete circle?
No. A ring road may completely surround a city, form only part of a loop or consist of several connected roads that together perform a ring-road function.
Is a ring road the same as a motorway?
No. Some ring roads are motorways, while others consist of expressways, ordinary roads or a mixture of road types. Motorway rules apply only where the road is legally designated as a motorway.
What is the speed limit on a ring road?
There is no universal ring-road speed limit. The applicable speed depends on the country, road classification, location and posted traffic signs.
How can you recognise a ring road?
Ring roads are usually indicated by route numbers, directional signs or the name of the ring. The signs may also show destinations that can be reached by travelling clockwise or anticlockwise around the urban area.
Can a ring road have intersections and traffic lights?
Yes. Ordinary ring roads may contain intersections, roundabouts and traffic lights. Fully controlled-access ring roads or motorway sections generally use grade-separated junctions instead.
Can pedestrians and cyclists use a ring road?
This depends on the road type and local access rules. They may use some ordinary-road sections but are normally prohibited from motorway sections and other roads where signs restrict access.
Which lane should you use on a ring road?
Follow the country's normal lane-use rules and any lane-direction signs. On multi-lane sections, choose the appropriate lane in good time when approaching an interchange or exit.
What should you do if you miss an exit on a ring road?
Continue safely to the next suitable junction or exit. Never reverse, make an unsafe U-turn or cross restricted areas in an attempt to return to a missed exit.

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