Time Zones
0Loading crowd target
0Loading crowd target
6correct to beat the crowd
97 free Time Zones trivia questions with answers — geography quiz, new questions added Oct 2026.
Every place on Earth once kept its own solar time, and it took railways, telegraphs and a great deal of argument to sort the planet into zones. The result is gloriously untidy: China runs on a single clock across five geographic zones, India and Nepal sit on half- and quarter-hour offsets, France keeps German wartime time, and Kiribati moved the International Date Line a thousand kilometres east so it could greet the year 2000 first. This quiz tours that history and its oddities: the Day of Two Noons in 1883, Sandford Fleming's 24 zones, why UTC is abbreviated the way it is, where leap seconds come from, what "Zulu time" means, who really proposed daylight saving, the Friday Samoa deleted in 2011, and the 3.5-hour jump at the Afghanistan–China border. Fifty questions from easy to hard, every answer sourced, each explanation adding one more detail for the next trip across the date line.
30 of 97 questions with answers and explanations. Play the quiz
Q 01Which imaginary line is the zero point for the world's time zones?
The prime meridian
The prime meridian. Delegates meeting in Washington in 1884 fixed it at Greenwich, partly because the United States had already built its railway time zones on that line.
Q 02Before standard time, clocks in which English city ran about ten minutes behind London's?
Bristol
Bristol. It lies about 2.5 degrees west of London, and the Sun takes four minutes to cross each degree; the clock on the city's Exchange still carries a second minute hand for the difference.
Q 03From 1852, which technology carried Greenwich time across Britain?
The telegraph
The telegraph. A master clock at Greenwich sent signals down the wires, and by the mid-1850s almost every public clock in Britain showed London time; the law caught up only in 1880.
Q 04Which colony adopted a nationwide standard time in 1868, 11½ hours ahead of GMT?
New Zealand
New Zealand. Its clocks kept that odd half hour until a wartime emergency put them forward all year round, a change made permanent in 1946 that left the country a round 12 hours ahead.
Q 05Which country set its clocks back 30 minutes in 2015 to shed a legacy of Japanese rule, then reversed it in 2018?
North Korea
North Korea. It created Pyongyang Time for the 70th anniversary of liberation from Japan, then moved back after a summit with the South so that both Koreas would share one clock again.
Q 06November 18, 1883, when US railroads reset their clocks, is remembered as what?
The Day of Two Noons
The Day of Two Noons. Railroad station clocks were reset as standard-time noon reached each zone, so a clock that had already passed midday by local sun time came round to noon again.
Q 07Which US state began observing daylight saving time statewide only in 2006?
Indiana
Indiana. For decades most of its counties stayed on standard time all year while those near Chicago and Evansville changed their clocks, so the gap between neighbours depended on the season.
Q 08Which federal department sets time zone boundaries in the United States?
Transportation
Transportation. A 1918 law gave the job to the Interstate Commerce Commission, then the only federal transport regulator, and Congress moved it across when the department was created in 1966.
Q 09Which Canadian railway engineer proposed a worldwide system of 24 time zones in the 1870s?
Sandford Fleming
Sandford Fleming. Railways had made town-by-town sun time unworkable, and he pressed his scheme until Washington hosted the 1884 conference at which nations agreed to take Greenwich as their common reference.
Q 10Which Atlantic Canadian island keeps its own time zone, half an hour ahead of the mainland beside it?
Newfoundland
Newfoundland. Its clocks follow the Sun at St. John's, the capital on its eastern tip, almost exactly three and a half hours behind Greenwich; as a separate dominion it kept that time when zones came in.
Q 11Which Himalayan country keeps one of the world's rare quarter-hour offsets, UTC+05:45?
Nepal
Nepal. Its time is reckoned from the meridian of Gaurishankar, a mountain east of Kathmandu, which is why its clocks sit an odd quarter of an hour off its neighbours'.
Q 12Which country briefly cut its 11 time zones to nine?
Russia
Russia. Dmitry Medvedev trimmed the map and kept summer time all year, saying clock changes even upset cows; after complaints about dark winter mornings, both reforms were undone in 2014.
Q 13Which country spans five geographic time zones yet keeps a single official clock?
China
China. Beijing time is the only official clock, so in the far west the Sun can be highest at three in the afternoon, and many people in Xinjiang keep an unofficial time two hours behind.
Q 21Which crewed outpost runs on UTC because it meets a sunrise or a sunset every 45 minutes?
The International Space Station
The International Space Station. With no natural day on board it is locked to a single clock, though crews launched from Baikonur used to arrive still adjusted to Kazakhstan time.
Q 22A "sol", about 40 minutes longer than a day on Earth, is a day on which planet?
Mars
Mars. Rover controllers have lived on Mars time themselves, starting work about 40 minutes later each day, a rolling jet lag they fought with naps and blue light boxes.
Q 23Which South American country kept a half-hour offset, UTC−04:30, from 2007 to 2016?
Venezuela
Q 14Which land border has the greatest time-zone jump on Earth, 3.5 hours?
Afghanistan–China
Afghanistan–China. The record jump, from UTC+04:30 to UTC+08:00, comes at one of the world's emptiest frontiers: a short mountain border whose crossing, the Wakhjir Pass, has no road.
Q 15Which large country keeps a single half-hour offset, UTC+05:30, across its whole width?
India
India. The single clock is a legacy of British rule, and the country is so wide that the Sun rises nearly two hours earlier in its far east than in its far west.
Q 16Tea gardens in which Indian state run an hour ahead of IST on "Bagan time"?
Assam
Assam. Its tea estates keep "bagan time" as an informal zone of their own because the Sun is up so early in the country's north-east.
Q 17Which letter stands for UTC in the lettered time zone system, giving UTC its radio nickname?
Z, hence "Zulu time"
Z, hence "Zulu time". Zulu is the radio alphabet's word for Z, and weather services around the world log their observations in Z time so that readings from different places line up.
Q 18Why is Coordinated Universal Time abbreviated UTC rather than CUT?
A compromise to match all languages
A compromise to match all languages. English word order gives CUT and French gives TUC, so the standard's designers picked one neutral abbreviation that favours neither language.
Q 19What is occasionally added to UTC?
A leap second
A leap second. First inserted in 1972, the extra seconds cause such trouble for computer networks that the world's metrologists voted in 2022 to stop adding them by 2035.
Q 20UTC is derived from which reference scale, a weighted average of hundreds of clocks?
International Atomic Time (TAI)
International Atomic Time (TAI). Set level with Earth-rotation time in 1958, it has since pulled more than half a minute ahead of UTC, because the planet's spin keeps slowing and atomic clocks do not.
Venezuela. President Hugo Chávez moved the official meridian by decree in 2007, putting the country half an hour behind its old time until the change was reversed in 2016.
Q 24France still keeps UTC+01:00 because of what historical event?
German occupation in World War II
German occupation in World War II. The occupiers put clocks on Berlin time in 1940, and a return to Greenwich time planned after the Liberation was dropped in 1945, so the wartime hour stayed.
Q 25Counting its overseas territories, which country spans the most time zones, 12 in all?
France
France. Its territories stretch from French Polynesia in the eastern Pacific to New Caledonia and Wallis and Futuna beyond the date line; counting its Antarctic claim would make 13.
Q 26The International Date Line roughly follows which meridian?
180°
180°. That meridian lies halfway round the world from Greenwich and mostly over open ocean; wherever it would split a country or an island group, the line swerves round, which is why it zigzags.
Q 27Crossing the date line eastbound does what to the calendar?
Moves it back one day
Moves it back one day. That is the twist in Around the World in Eighty Days: travelling east, Phileas Fogg had gained a day without noticing, so he won his bet after all.
Q 28Which 1522 voyage first confirmed that circumnavigators lose a day?
Magellan–Elcano expedition
Magellan–Elcano expedition. Putting in at Cape Verde after three years sailing west, the survivors found their meticulous log a day behind: it said Wednesday, and the islanders said Thursday.
Q 29The Philippines sat a day behind its Asian neighbours for 323 years because of its galleon trade with where?
Acapulco, Mexico
Acapulco, Mexico. The islands were governed and supplied from Mexico, so they kept the American date until the governor struck 31 December 1844 from the calendar altogether.
Q 30Which island pair in the Bering Strait does the date line pass between?
The Diomede Islands
The Diomede Islands. Big Diomede is almost a full day ahead of Little Diomede, a few kilometres to its east, so the pair are nicknamed Tomorrow Island and Yesterday Island.