The devastating tsunami that killed more than a quarter of a million people on St Stephen's Day, 2004 was the deadliest tidal wave disaster in recorded history.
The tenth anniversary memorial services will take place later this week in some of the worst-hit areas of Southern Asia.
A massive undersea earthquake with a magnitude of 9.0 occurred off the west coast of Sumatra, Indonesia, early on December 26 of that year.
It triggered a series of devastating tsunamis along the coasts of 14 nations bordering the Indian Ocean.
The huge waves travelled thousands of kilometres, destroying everything in their path. Some waves were as high as 30 metres when they crashed into land.
Indonesia was hardest-hit, followed by Sri Lanka, India and Thailand.
Most coastal communities were caught unawares as huge waves swept in from the sea, drowning people in their thousands and destroying their towns and villages.
In Indonesia alone, more than 130,000 died. The region of Banda Aceh bore the brunt of the raging salt-water monster with tens of thousands drowned within minutes. A 2,600 tonne ship was flung more than two kilometres inland in the devastating surge.
Around the world, television news bulletins carried reports of the terror and devastation of the catastrophe into the homes of families who had come together to celebrate the festive season.
Breaking news showed the latest horrors as survivors recounted how locals and tourists alike were engulfed in the nightmare of one of the world's worst natural disasters.
In some resorts, the entire staff and guests of hotels were drowned as walls of water came thundering inland.
Four Irish tourists lost their lives. The first of the Irish victims was Dublin woman Eilis Finnegan.
Her body was found in Thailand. The 27-year-old United Airlines air hostess, from Muskerry Road in Ballyfermot, had been on the beach at Phi Phi island with her boyfriend Barry Murphy, who was 29 and from Castleknock in Dublin. Barry survived.
Other Irish who lost their lives were Lucy Coyle (29), Killiney, Co Dublin; Michael Murphy (23), Knockbawn, Blackwater, Co Wexford; and Conor Keightley (31), Cookstown, Co Tyrone. All were killed in Thailand.
Families of holidaymakers in some other European countries were hit very hard. Sweden lost 543 of its citizens, while 539 German tourists were killed.
One of the reasons for the incredibly high death toll was that no one had any warning that the waves were coming, even though some countries were hit hours after the quake.
There was no tsunami early warning system in the Indian Ocean nor a way of letting people know even that a tsunami had been detected.
One of the most urgent tasks of the disaster management programmes was the swift burial of bodies to prevent the spread of disease. However, in many areas, bodies were kept in cold storage for several months as DNA evidence and other methods were used in an attempt to identify as many of the victims as possible.
Some families had to wait more than seven months for confirmation that their loved one's remains had been finally identified.
The Irish humanitarian response to the disaster was remarkable. Around €80m was donated by the Irish public in a wide range of fund-raising events.
The Irish Government gave a further €20m in aid to the stricken countries. The €100m response from such a small country was warmly welcomed by agencies helping the victims.
Almost €6.5m of government tsunami aid was spent on projects in Indonesia while Sri Lanka got almost €4.8m.
The bulk of the money was administered by Development Cooperation Ireland, the government's programme of assistance to developing countries.
A large amount of the money, was given charitable agencies such as Concern, Goal, Trocaire, Oxfam and Christian Aid. Burma, India, Thailand, the Maldives and the south Asia region all received monies from the Irish Government.
A host of innovative and generous projects were developed by Irish individuals around the country. The international community pledged more than €11bn to disaster relief and re-development. The World Food Programme provided food aid for more than 1.3 million people affected by the tsunami.
On the first anniversary of the disaster, large numbers of people attended memorial services for victims in all the countries affected. Several relatives of victims travelled to Thailand for the services.
This week, there are many people from around the world making their way to the places where their loved ones were lost forever. Although a decade has now passed, the sense of loss for those most directly affected continues.