50 Fun Facts About Traffic

Where was the world's first traffic signal, a gas-lit semaphore, erected in December 1868?

It stood outside the Houses of Parliament near Westminster Bridge and was operated by a policeman.

What fate befell the 1868 Westminster gas signal only weeks after it was switched on?

A gas leak set it off and badly injured the policeman working it; Britain did without traffic lights again until 1929.

In which city did the American Traffic Signal Company install an electric traffic light at Euclid Avenue in August 1914?

It had red and green lights and a buzzer, and was wired so that conflicting signals could not show at once.

Which inventor patented a manually operated three-way traffic signal with moving arms in 1923?

Morgan, also known for an early gas mask, reportedly sold the rights to General Electric.

Which country decreed in 1973 that the 'go' light should be the bluest possible shade of green?

The word for the light there was traditionally the same word used for blue, so the tint was changed to match the name.

In which city did Sergeant Harry Jackson make the first stop sign from plywood in 1914?

He was working as a traffic guard at a busy intersection and simply wanted drivers to halt.

Before 1954, US stop signs carried their lettering on a field of which colour?

Fade-resistant red materials did not exist yet, so red only took over once the 1954 manual specified white lettering on a red field.

Which traffic reformer redesigned New York's Columbus Circle in 1905 as an early one-way traffic circle?

Eno also wrote the first traffic code for New York City and never learned to drive.

The United Kingdom adopted which roundabout rule nationwide in 1966?

Before the change, cars already on the circle could jam solid as newcomers pushed in from every arm.

Swindon's Magic Roundabout, built in 1972, consists of how many mini-roundabouts arranged in a circle?

Its official name was originally County Islands, and it follows a design by Frank Blackmore of the Transport and Road Research Laboratory.

In the mid-2010s about 3% of all modern roundabouts in the US were in which suburb north of Indianapolis?

The city has replaced signal after signal with circles and calls itself the roundabout capital of the United States.

Britain's Locomotive Act of 1865 limited self-propelled vehicles to what speed through towns?

The same law required a man to walk ahead carrying a red flag, which is why it is remembered as the Red Flag Act.

At roughly what speed was Walter Arnold, Britain's first convicted speeder, clocked in 1896?

He was in a 2 mph zone and was caught by a policeman on a bicycle.

Jacob German, arrested in Manhattan in May 1899 for doing 12 mph on Lexington Avenue, worked as what?

His is usually cited as the first speeding arrest in the United States; the first paper ticket came in Dayton in 1904.

The Emancipation Run of November 1896, celebrating a new 14 mph car limit, went from London to which seaside town?

Thirty vehicles took part, and the veteran car run is still held on the same route every November.

Which country moved all its road traffic from the left side to the right at 5 a.m. on 3 September 1967?

The change was called Dagen H, for Högertrafik, and only 157 minor accidents were reported that day.

In the 1955 referendum held before Dagen H, what share of voters wanted to keep driving on the left?

Parliament pushed the change through anyway because neighbours drove on the right and most Swedish cars were already left-hand drive.

Which Pacific nation switched from right-hand to left-hand traffic in 2009?

The move let islanders import cheaper used cars from Australia, New Zealand and Japan.

Which country built the 1924 Autostrada dei Laghi, called the world's first motorway?

Engineer Piero Puricelli charged tolls from the start to pay for it, and the stretch near Milan has since been widened to five lanes each way.

Which US president signed the Federal Aid Highway Act of 1956 that created the Interstate system?

A punishing 1919 cross-country army convoy and the German autobahns he saw in the war both shaped his thinking.

Route 66, established in 1926, ran from Chicago to which California city?

It covered 2,448 miles across eight states and was formally removed from the US Highway System in 1985.

After the 1958 Preston By-pass, which full-length motorway opened in Britain in 1959?

It opened with no speed limit, no crash barriers and no lighting, and became a favourite of touring bands heading for Watford Gap services.

The world's first installed parking meter went into service on 16 July 1935. Where?

Lawyer and publisher Carl Magee pushed for it, and one of the first tickets went to a preacher who said he had only left to get change.

The 12-day, 100 km traffic jam of August 2010 was on a coal-truck highway to which Chinese city?

Roadworks had halved capacity, and some drivers reported moving only a kilometre a day.

'Carmageddon' was the nickname for a July 2011 weekend closure of which Los Angeles freeway?

Crews were demolishing the Mulholland Drive bridge; traffic turned out lighter than feared and cyclists beat a JetBlue flight across town.

The word 'gridlock' spread from a New York City traffic engineer's memo during which 1980 event?

Sam Schwartz titled his emergency plan the 'Gridlock Prevention Plan' and newspapers picked the word up.

Percy Shaw, who patented the reflective cat's eye road stud in 1934, came from which Yorkshire town?

He was inspired by tram rails glinting at night, and a rubber wiper cleans each reflector whenever a tyre presses it down.

The world's first zebra crossing was installed in 1951 in which English town?

The name is credited to future prime minister James Callaghan, who saw the striped design and remarked that it looked like a zebra.

Belisha beacons are named after Leslie Hore-Belisha, who held which post in 1934?

They gave pedestrian crossings a warning signal fifteen years before any crossing got traffic lights of its own.

Introduced in the UK in 1969, the pelican crossing takes its name from a compression of which phrase?

It followed the failed panda crossing, and since October 2016 no new pelicans may be installed as puffins replace them.

Around 1910, when 'jaywalker' entered American slang, what did the word 'jay' mean?

Motoring lobbies pushed the term to shift blame for accidents onto pedestrians, and Los Angeles passed the first major ordinance in 1925.

Which Australian state became the world's first jurisdiction to make seat belts compulsory, in 1970?

South Australia followed the next year; the UK waited until 1983 and New York became the first US state in 1984.

Nils Bohlin, a former Saab ejection-seat designer, invented the three-point seat belt in 1959 for which carmaker?

The company opened the patent to everyone in 1968, and US regulators estimate belts save about 15,000 lives a year there.

Breathalyzer inventor Robert Borkenstein was a captain in which state's police force?

An earlier device from the same state, Rolla Harger's 1931 Drunkometer, made drivers blow into a balloon.

Charles Scanlon invented the traffic cone in 1943 to replace wooden tripods in what job?

Cones reached Britain in 1958 to replace paraffin lanterns during construction of the Preston By-pass.

The first edition of Britain's Highway Code, published on 14 April 1931, cost how much?

Its 21 pages included the arm signals drivers and police were expected to use; illustrated road signs only arrived in the 1934 edition.

The Pan-American Highway is broken by the Darién Gap, between Panama and which country?

The gap is about 106 km of marsh and forest, and no car ferry has run across it for decades.

The Yungas 'Death Road', called the world's most dangerous in 1995, is in which country?

Unlike the rest of the country, drivers keep left there so they can judge how close their wheels are to the edge.

Which city's 1975 Area Licensing Scheme was the world's first urban congestion pricing?

It swapped paper licences for electronic gantries in 1998, decades before London's £5 charge began in 2003.

Braess's paradox, that adding a road can slow traffic, is named after Dietrich Braess, a German what?

Seoul's traffic improved after the Cheonggye Expressway was demolished, and closing part of Broadway in 2009 sped up Manhattan.

Which company bought the Israeli-founded navigation app Waze in June 2013?

The price was a reported $1.3bn, and its roughly 100 employees received about $1.2 million each on average.

A grooved stretch of Route 66 in Tijeras, New Mexico plays which song when driven over at exactly 45 mph?

Lancaster, California has a similar road that hums part of the William Tell Overture.

The United States imposed a national 55 mph speed limit in 1974 in response to what?

The Emergency Highway Energy Conservation Act aimed to save fuel; the limit was fully repealed in 1995.

Which city's stretch of Highway 401 is North America's busiest highway?

It is officially the Macdonald–Cartier Freeway, and some stretches carry more than 400,000 vehicles a day.

The Katy Freeway, at 26 lanes believed to be the widest in the world since a 2008 expansion, serves which city?

Its count includes frontage roads; the most undivided lanes in one direction is nine.

Ward's estimated how many motor vehicles were in use worldwide in 2019?

The fleet passed one billion around 2010, and the US runs about 850 vehicles per 1,000 people.

The advisory speed on unrestricted stretches of the German autobahn is what?

A 2017 study found roughly 70% of the network carried only this advisory limit.

Traffic engineers liken widening roads to fight congestion to loosening your belt to cure what?

Studies find a 10% increase in lane miles can generate a 10% rise in driving within a few years, the effect known as induced demand.

Who developed the first electric traffic light in 1912, while working as a Salt Lake City policeman?

The first four-way, three-colour light with an amber caution lamp came in 1920 from Detroit's William Potts.

In Quebec's horizontal traffic lights, what shape is the amber aspect?

Red is a square, usually doubled at each end of the fixture, and green is a circle, so colour-blind drivers can read the signal by shape.