Built-up area (Highway Code)

In 2018, mainland UK became a member of the Vienna convention on road traffic which consider that the concept of built-up area should be defined by the domestic legislation.

Section 81 specifically makes it an offence for a person to drive a motor vehicle at a speed of more than 30 mph on a restricted road.

However, street lighting (for the purposes of determining whether or not a road is a restricted) is not necessarily limited to street lamps, but may extend to lighting provided by authorities or parish councils.To avoid confusion that could arise if some 30 mph zones were 'street-lit' and some were not, DfT guidance goes onto say:[citation needed] Direction 11 of The Traffic Signs Regulations and General Directions 2002 (TSRGD 2002) defines the requirements for the placing of speed-limit repeater signs.

This states that speed-limit repeater signs cannot be placed along a road on which there is carriageway lighting not more than 183 metres apart and which is subject to a 30 mph speed limit.

In Northern Ireland, the Highway Code forbids the use of the horn within built-up area between 2330 and 0700, except in case of danger,[4] consistently with article 28 of the Vienna convention.