Nations around the world are ringing in the new year and bidding farewell to a decade that will be remembered for the rise of social media, the Arab Spring, the MeToo movement and Donald Trump.
Here is a look at how the world is ushering in 2020.
Crowds across Europe welcomed 2020 with fantastic displays over capital cities across the continent.
France, Germany, Greece, Turkey and Lithuania saw the skies lit up with fireworks as thousands of revellers cheered in the new year.
Crowds gathered across India to welcome in the new year, from the celebrated Gateway of India in Mumbai to the streets of Bangalore.
Huge crowds of North Koreans gathered in Pyongyang to count down to midnight and welcome in the new year with a spectacular firework display.
Russians began the world's longest continuous New Year's Eve with fireworks and a message from President Vladimir Putin urging them to work together in the coming year, broadcast on television just before the stroke of midnight in each of Russia's 11 time zones.
But one holiday tradition is missing in Moscow this year — a picturesque layer of snow – after the capital enjoyed an unusually warm December.
Tens of thousands of revellers in the capital Jakarta were soaked by torrential rains as they waited for New Year's Eve fireworks, and festive events along coastal areas near the Sunda Strait were dampened by a possible larger eruption of Anak Krakatau, an island volcano that erupted last year just ahead of Christmas Day, triggering a tsunami that killed more than 430 people.
Revellers and pro-democracy protesters alike flocked to sites across the territory to see out a troubled 2019.
The semi-autonomous Chinese city has toned down the usually raucous celebrations this year, and the traditional fireworks display over Victoria Harbour has been cancelled, while some roads have been closed and barriers set up in the Lan Kwai Fong nightlife district.
Thousands of South Koreans filled cold streets in central Seoul for a traditional bell-tolling ceremony to send off an exhausting 2019 highlighted by political scandals, decaying job markets and crumbling diplomacy with North Korea.
People flocked to temples and shrines to mark the first new year of the Reiwa era.
Under Japan's old-style calendar, linked to emperors' rules, Reiwa started in May after Emperor Akihito stepped down and his son Naruhito became emperor.
More than a million people descended on a hazy Sydney Harbour and surrounding areas as the city went ahead with its famous fireworks display after being granted an exemption to a total fire ban, amid devastation caused by wildfires across the country. The event began with a family-friendly display, ahead of the midnight showstopper.
President Xi Jinping used his new year address to call for Hong Kong to return to stability following months of pro-democracy protests, saying a peaceful, harmonious environment is key to the Asian financial hub's prosperity.
While fireworks erupted at midnight from Mount Vaea, overlooking the capital Apia, the end of 2019 was a time of remembrance after a measles epidemic claimed 81 lives, mostly children under five.
Major cities greeted the new year with fireworks, and saw off 2019 without regret after a gunman identified killed 51 people at two mosques in Christchurch, and an eruption of volcanic White Island killed at least 19 tourists and guides.
The island nation covering more than three million square miles of the Pacific was one of the first countries to welcome a new decade where it will be on the front line of the battle against climate change, facing drought and rising sea levels.