The men of Harland and Wolff put the final touches to the ship, before she undertook several hours of sea trials in Belfast Lough and set sail for Southampton in the evening.
Five Harland & Wolff tugs were used to carefully guide her down the channel of Belfast Lough, as crowds gathered to watch her passage.
Titanic was a floating hotel for the 2,200 passengers on board, and those sailing as first class had only the best on their short journey.
"It was a very prestigious journey but of course the first class passenger list read like a 'who's who' of international society," said historian Eamon Phoenix.
Third class cabins on the Titanic were also much more luxurious than in other ships of the time, with running water in the cabins.
Martina Devlin's great-uncle died on the Titanic, and she believes he was part of the dancing and music among the lower classes on board.
"I like to think that my relatives enjoyed their last few days," she told UTV.
Una Reilly, from the Ulster Titanic Society, said Belfast should be proud to have reclaimed the story of the doomed liner, which was the biggest man-made moving object of the planet at the time.
She was part of the skyline back then, in the early part of the 1900s, very much as the cranes are today.
Una Reilly on UTV Live
The Titanic was originally due to depart from Belfast on 1 April 1912, but her departure was postponed for one day due to the weather conditions.
The ship left Southampton on her maiden voyage on 10 April - but days later, a few hundred miles south of Newfoundland, she hit an iceberg.
On 15 April 1912, the passenger liner sank in the north Atlantic Ocean with the loss of over 1,500 passengers.
On Saturday, the Titanic Belfast visitor attraction, which tells the story of Titanic throughout nine galleries, opened its doors.
The design of the building is based on the bow of the Titanic and has been built right beside the slipway where the liner was floated in 1911.
On Monday night, the Thompson Dry Dock area was transformed into an open-air cinema for an extra special screening of 'A Night To Remember.'
Hundreds of people watched the screening of the iconic film, produced by one of UTV's founders William MacQuitty, which was hosted by Belfast Film Festival.
The First and Deputy First Ministers were there - with Martin McGuinness revealing his family's double connection with the doomed liner.
He has discovered that both his great uncle and grandfather worked on kitting the ship out.
Mr McGuinness explained: "I was talking to a cousin of mine from Strabane and she was telling me that her mother told her that her grandfather, also my grandfather, who was living in the same house also worked for a shorter period than Hugh Rooney on the Titanic.
"If that is validated at a later stage that is two fairly incredible links for someone who comes from Derry city and the north west."
On Tuesday night the dry dock will once again be lit up, this time for the premiere of 'Saving The Titanic,' starring NI actor Ciaran McMenamin.
There will be seating for over 500 people.