Titanic relatives from as far away as Canada have praised their brave ancestors during a ceremony.
Helen Frost from Toronto travelled with her granddaughter Alex Aaronson, six. Alex's great, great grandfather, Artie Frost, 38, was an engineer in Belfast and a member of the guarantee group which Harland and Wolff sent with the ship to record its performance.
Helen Frost said: "It is important to be here because we are very proud of Alex's great, great grandfather.
"He was a brave, brave man and he went down with the ship."
Dr Robert Ballard, who discovered the wreck in 1985, said engineers worked to keep the lights on until the end, helping those in the lifeboats avoid being dragged back towards the ailing Titanic and potentially pulled under.
Ms Frost said: "We felt it was important to be here. We are very proud, we have been very impressed, Belfast has done a wonderful job, it is just lovely."
Alister McReynolds' distant cousin William McReynolds, 22, was an electrical engineer on board.
It was his first voyage at sea. He was unmarried and lived in Belfast with his parents.
Mr McReynolds said: "They kept the lights on to the end so I like to think that he was part of that.
"He must have been a forward-looking person as there cannot have been that many of those electrical engineers in 1912."