Descendants, dignitaries and members of the public came together to remember the 344 men and boys who died at Pretoria Pit on December 21, 1910.
They gathered at the memorial on the site, which is on the border of Atherton and Westhoughton, for a service led by former Bolton West MP Julie Hilling.
There was music by Jim Berry, from the Houghton Weavers, and Andrea Finney read a poem.
Wreaths and flowers were then laid at the memorial, which bears the names of everyone who died in the disaster.
Hundreds of people once worked at the pit, but disaster struck when there was an underground explosion caused by a build-up of gas.
Of the 347 who went down no 3 Bank pit that day, only four came out alive.
Sadly, one of the survivors succumbed to his injuries less than 24 hours later, while a second died of pneumonia a week later.
13. Pretoria Pit commemoration service
A red, white and green wreath among the many tributes Photo: Kelvin Lister-Stuttard
14. Pretoria Pit commemoration service
Andrea Finney reads a poem Photo: Kelvin Lister-Stuttard
15. Pretoria Pit commemoration service
A moving memorial service paid tribute to the men and boys who died Photo: Kelvin Lister-Stuttard
16. Pretoria Pit commemoration service
Former Bolton West MP Chris Green at the service Photo: Kelvin Lister-Stuttard