Of the 610 passengers and 123 crew on board for the sailing, 53 people perished.
Because of its proximity to the city of Wellington, the disaster became known as one of the first major events to be captured by television news crews in New Zealand as it happened.
* Watch a news report from the time on NZ on Screen here.
The godson of the ferry's master says he has been fighting a battle to make public the truth about what happened.
Murray Robinson is the godson of Gordon Robertson, who was in charge of the ship when it hit rocks and began to sink in the Wellington harbour during a storm in 1968.
He often sees reports of what happened that day and says they aren't entirely accurate.
These include "that he was asleep that morning until it was too late, that he gave engine orders that caused the ship to be thrown against the reef, that he stood around doing nothing, that he gave the order to abandon ship when it was far too late".
Mr Robinson says he has spent the last 20 years researching what happened at the time, and has put together a website for those interested.
However, it's not just the sinking of the Wahine that will be remembered today, but also the storm that caused it.
Museum of Wellington City and Sea's Kim Young says today will be a special day for many.
"It's 45 years on, two generations on, yet the memories of the Wahine storm and the sinking of the Wahine are still vivid in the minds of many Wellingtonians."
* Read the Herald's live news blog here.