A rare opportunity to dive to the Japanese M24 midget submarine wreck off Sydney's northern beaches will be offered to a dozen lucky people.
For the first time, a ballot will decide two groups of six divers who will descend to the historical site in November, some 75 years after the submarine attacked Sydney Habour during World War II.
In 1942, the M24 was one of three midget Japanese subs - each with a two-member crew - to enter the harbour.
The two others were detected but the M24 sank the navy depot ship HMAS Kuttabul, killing 21 sailors.
The six Japanese submariners in the three midget submarines also died.
NSW Heritage Minister Gabrielle Upton says the site is significant in Australian history because it's the "one and only time Sydney has come under attack".
"Giving people the chance to see this site from a respectful distance will help highlight the heritage significance of the site," Ms Upton said in a statement on Friday.
The M24 wreckage was protected after the No Frills Divers group discovered it in November 2006, with penalties of up to $1.1 million for disturbing the site.
The November dive will be conducted according to strict protections under federal and state laws at a depth of 54 metres.
Five years ago then-Environment Minister Robyn Parker announced the site would be open for its first trial dive to mark the 70th anniversary of the attack.
However, the open dive never eventuated.
