The 100th anniversary of the sinking of the Titanic is being remembered at a number of a special events, including one in the ship's birthplace Belfast.A memorial service for the 1,500 people who died was held at the North Atlantic wreck site on cruise ship MS Balmoral, which is retracing the Titanic's route.
A minute's silence was held and wreaths were cast into the sea at the moment the Titanic sank.
And a plaque featuring the names of those who died was unveiled in Belfast.
The ship, which at the time was the largest vessel in the world, was built in the city.
The plaque, in the Titanic Memorial Garden, lists the names of those who died in alphabetical order.
At the sceneIn the middle of the Atlantic a ship's whistle sounded to mark exactly 100 years since the Titanic struck an iceberg.
At that moment passengers stood in silence on the decks all around the MS Balmoral looking out into the darkness.
Hundreds of miles from land some imagined the despair they would have felt being lowered into the sea in a lifeboat. Others thought of their relatives who had drowned here a century earlier.
After the excitement of the departure and earlier days at sea, the ship seemed eerily quiet.
In the cold of the north Atlantic one person described the atmosphere as "almost ghostly".
The Balmoral had traced the route of the Titanic from Southampton to the spot where the ship sank. There it was met by another vessel that had travelled from New York, the destination Titanic never reached.
The ships sat side-by-side thousands of metres above the wreckage, allowing passengers to pay tribute at what some relatives regard as a grave site.
Thousands attended or listened to the Belfast service, which was held at the city hall.Una Reilly, head of the local Titanic Society, said: "We are all proud of this ship. What happened was a disaster, she was not."
And a memorial service was held in Southampton, from where the ship set sail five days before its sinking.
The anniversary has been marked in a number of services across the UK.
- A service was held in Godalming, Surrey, to commemorate Titanic's chief telegraphic officer, Jack Phillips, who died after staying at his post until his equipment failed
- A plaque honouring Commander Harold Lowe was unveiled at his home town of Barmouth, Gwynedd, because records show he commanded the only lifeboat to look for survivors, pulling four people from the freezing water
- The 14 Guernsey passengers who lost their lives in the accident were commemorated with the unveiling of a plaque
- And a service described as an act of remembrance will be held at Liverpool Cathedral later
Jane Allen's great-uncle, Thomas Pears, was one of those who died.
Explaining the emotions she felt during the service, she told the BBC: "It was just so eerily quiet.
"And then you look down over the side of the ship and you realise that every man and woman who was not fortunate enough to get into a lifeboat had to make that decision of when to jump or to stay with the ship, until the lights went out.
"And when the lights went out it must have been horrendous. We witnessed that tonight."
Melinda Norris, whose relative Charles Lightoller was a surviving crew member, said: "You still get a chill just looking at that water, imagining you have to go into it.
"We've been listening to the names of the 1,500 people who died.
"It's just an unimaginable amount of suffering took place here, so it's surreal to be here."
Richard Hyman's great-grandfather was also on board Titanic and lived to tell the tale.
Mr Hyman said: "You imagine it's pitch black, freezing cold, nothing is anywhere near you other than an iceberg.
"The fear that must have been with all those people who were either stuck on the ship or in a lifeboat, not knowing whether they were going to survive or not.
"And people did freeze to death as well, even though they'd survived the disaster."
Another cruise ship, Azamara Journey, which has travelled from New York, also held a service at the site of the disaster, which occurred 400 miles (640km) off the coast of Newfoundland.
The sinking is also being remembered in other parts of the globe including New York, which had been the Titanic's intended destination.
About 1,300 passengers, ranging from millionaires to poor emigrants, and about 900 crew were on board the Titanic when it sank on its maiden voyage.
The ship left Southampton on 10 April 1912. It headed to Cherbourg in France and Queenstown - now Cobh - in the Irish Republic before heading for New York.
The ship hit an iceberg at 23:40 (Ship's Time) on 14 April 1912, and sank two-and-a-half hours later.