Cities mark the early hours of 2017 with a big bang
Thousands of people gathered in Dublin last night amid a riot of colour and noise to welcome in the New Year.
And all around the country revellers made the most of the final hours of 2016.
The Irish diaspora also made their mark in various parts of the world, as 2017 was welcomed with traditional fireworks displays, and hearty renditions of Auld Lang Syne.
Millions of people around the globe enthusiastically embraced all the optimism a new year brings, with a vast array of festivities and celebrations.
Here at home, one of Dublin's landmark locations was specially illuminated, as aerial acrobats and street performers thrilled the crowds.
Luminosity, a 3D light projection display, brought a world of wonder to wide-eyed children who stared in amazement as the Custom House was turned into a dazzling video canvas.
The night sky was immersed in a fresco of light, while blazing graphics lit up the building.
As the clock struck 5pm, a crane hoisted an Irish currach high above an enraptured crowd, as a kaleidoscope of colour lit up the night sky. Then the spotlight turned to six drummers - each standing precariously on the roof of the Custom House - as they thrummed their instruments in time to the music.
The colourful spectacle ended with a jaw-dropping acrobatic show as aerialists and abseilers swung into action high above the watching crowd.
The performers enthralled both young and old as they blended stunning mid-air contortions with contemporary dance, while seemingly sailing through the night sky.
The 3Countdown Concert at St Stephen's Green South kicked off at 8pm, headlined by Irish rock band Walking on Cars.
A huge crowd rang in the New Year, bopping to the sounds of the star-studded line-up.
The musical feast featured The Blizzards, Brian Deady, and Little Hours, and took spectators all the way through the countdown to that all-important midnight moment.
Billed as New Year's Festival Dublin, the three-day citywide festival, now in its third year, runs until tonight.
A special New Year's Day concert, featuring the Dublin Gospel Choir, plus the Garda Band, will take place today on St Stephen's Green at 2pm.
Meanwhile, celebrations to mark the New Year had their usual distinctive glow in other parts of the world.
However, the spectre of terrorism hung heavy in the air and a number of major cities stepped up security for the festivities.
Some 3,800 police officers were on duty in central London, blocking a number of major arteries to the city after a year in which attackers drove lorries into crowds in Berlin and Nice.
New Zealand was one of the first countries to ring in 2017, and crowds gathered in Auckland to sample a multi-coloured fireworks display.
In Australia, Sydney Harbour, as is traditional, provided the backdrop to a spectacular show.
Seven tons of fireworks made the landmark Harbour Bridge rain purple in a tribute to the late singer Prince as revellers soaked up the atmosphere. "This year, sadly, we saw the loss of many music and entertainment legends around the world," fireworks co-producer Catherine Flanagan said.
More than $1m worth of fireworks were launched in front of more than 1.5 million people - with the usual sprinkling of Irish expatriates providing their own distinctive touch to the occasion.
Hong Kong also welcomed in the New Year with a firework display over Victoria Harbour.
The last places on Earth to observe 2017 were remote uninhabited US outposts, including Baker Island and Howland Island.
Closer to home, various locations around Ireland conducted the countdown to 2017 in style. In Galway, electro musician Daithi, singer Elaine Mai and band Oh Boland hit all the right notes at the iconic Roisin Dubh music venue.
Further south, the country music singer and Wagon Wheel hitmaker Nathan Carter set some seasonal sounds in the INEC in Killarney, Co Kerry.
And in Mayo a number of hardy enthusiasts headed to Achill Island for a night with a difference.
Champagne corks were popping when they gathered on Minaun hill, where they sampled the symbolism of a final 2016 sunset as it slowly disappeared on a distant Atlantic horizon.