The ship will be leaving Southampton at 1500GMT (1000EDT) and will set sail via Cherbourg in north-west France before sailing to Cobh on Ireland's south coast and then to the spot where on April 15, 1912 the White Star-owned liner collided side-on with a huge iceberg and took two-and-a-half hours to plunge to a watery grave for more than 1,500 souls.
Many of the relatives on board MS Balmoral are dressed in period attire. The ladies are adorned in long evening dresses and American full-length day dress and the gentlemen have chosen to wear the black-suited attire worn by the gentry a century ago.
The ship is carrying 1,309 passengers - the same number as were on the Titanic - it is due to reach the wreck site on Saturday (April 14) for a service. There will then be a solemn memorial service held on the deck at 2340 GMT (1840EDT) - the exact time ship the hit the iceberg exactly 100 years on. Another service will be held at 0220 GMT (2120EDT) to mark the moment the "unsinkable" ship tore in half and plunged to the ocean floor on that dark, moonless fateful night, reports Huffington Post
Many of the relatives have taken wreaths of flowers and family artefacts in memory of those who died. Some will toss the wreaths overboard at the wreck site during the dark-night memorial service. There are relatives from more than 20 different countries on board the Balmoral. Also included are many relatives of some who survived the Titanic when the Carpathian came to its rescue. Many on board are authors, journalists, historians and those simply fascinated by the Titanic story. A tragedy that has captured the world's fascination for a century.
The passengers will even eat meals from the Titanic's original menu
and lectures will be given by historians and Titanic experts, reports the BBC
There will also be a band similar to the one they played on the Titanic. Jane Allen is a relative of Tom Pears. Tom was Jane's great uncle and she is among passengers who have paid up to £6,000 ($9,000) to join the commemorative voyage. She said:
I don't think it's ghoulish or macabre at all, I've been to the World War II and I cemeteries in various places across the world. I think it's always important to remember.
Once the Balmoral has had the commemorative service at the wreck site it will travel to Nova Scotia where many of the bodies recovered from the wreck were taken and buried. The ship will sail on its journey to New York City, the destination the Titanic failed to reach.