In London, more than 100,000 people gathered on the banks of the River Thames for a 12-minute pyrotechnics extravaganza.
More than 10,000 fireworks lit up the sky during the sold-out event, which received cheers from the crowd.
They were accompanied by the music of Aretha Franklin, Annie Lennox, Ariana Grande, Dua Lipa and Florence Welch, with the second half of the show commemorating 100 years of women having the right to vote.
Jubilant crowds were also treated to Big Ben’s bongs at midnight, with the famous clock’s four-year-long renovations temporarily put on hold for the occasion.
Although there were fewer police at the event than last year, security was still tight, with barriers and armed police patrolling a city which suffered four terrorist attacks in 2017.
Celebrations were marred by rail strikes – with a walkout by South Western Railway staff frustrating the plans of those seeking to travel into the UK’s busiest station, Waterloo.
The industrial action covered the period when many people would be trying to get home after the fireworks display.
In Edinburgh, about 75,000 were at Hogmanay celebrations, despite gusts of up to 76mph in parts of Scotland during the afternoon.
Rag’n’Bone Man headlined Concert in the Gardens, with Declan McKenna and Nina Nesbitt as support acts.
The Human League, Sacred Paws, Treacherous Orchestra and Huey Morgan also performed to crowds on three Street Party stages.
Fireworks were launched from Edinburgh Castle at 9pm, 10pm and 11pm – building up to a nine-minute finale at 12am.
Image:In Yogyakarta, Indonesia, the city’s skyline was illuminated by fireworks Image:Somalis danced as they celebrated the new year in Mogadishu, Somalia Image:Fireworks exploded over the skyline of Minsk, Belarus Image:Thousands of people gathered in Istanbul, Turkey, to countdown to 2018 Image:Fireworks were seen over the Kremlin in central Moscow Image:The fireworks had to compete with the rain at Marina Bay in Singapore Image:Hong Kong’s Victoria Harbour welcomed the New Year with fireworks Image:As did those gathered at an amusement park in Pasay, Metro Manila, in the Philippines Image:Sydney, Australia, had a fantastic pyrotechnics display Image:New Zealand’s largest city Auckland was the first major centre to see 2018 Image:In Nairobi, Kenya, they counted down to New Year’s Day at Kenyatta International Convention Centre Image:People watched the first sunrise on New Year’s Day at a beach in Tokyo, Japan Image:At least 100,000 people gathered on the Thames for London’s display Image:Berlin’s Brandenburg Gate was the scene for New Year festivities in Germany Image:On Nungwi Beach in Zanzibar, Tanzania, they waited for 2018 to arrive Image:Downtown Beirut was lit up as thousands celebrated in the rain Image:Pyongyang had fireworks in this photo from North Korea’s Korean Central News Agency Image:Fireworks lit up the Atomium building, a famous metal structure in Brussels, Belgium Image:People danced during the New Year’s celebrations in Mumbai, India Image:Fireworks exploded over the ancient Parthenon temple at the top of the Acropolis hill
Celebrations have been taking place around the world – and New Zealand was first to welcome in 2018, with fireworks focused around Auckland’s Sky Tower.
The Australian city of Sydney followed, keeping up its reputation as having one of the world’s best pyrotechnics displays centred on Harbour Bridge. Turnout was healthy to say the least, with an estimated 500,000 spectators in attendance.
Colourful shows in Hong Kong, Beijing, Paris and Berlin followed – with Dubai opting to mark the New Year with an extravagant lights show at the world’s tallest building, the Burj Khalifa.
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All eyes now are on the States, with enthusiastic crowds flocking to New York City as midnight approaches.
Revellers in Times Square have been urged to wrap up warm as temperatures of -11C are forecast, making it the coldest New Year’s Eve since 1962.