A 20-million-year-old whale fossil has been dug up from an Australian beach after a family stumbled across the extremely rare, “mind-blowing” relic while they were on vacation.

The remnants of the ancient vertebrae — believed to be one of the largest whale fossils ever found Down Under — was recovered from under about 1.5 feet of sand at Ocean Grove Beach in Victoria on Thursday.

Paleontologists were alerted to the monumental find after a family of five spotted part of the fossil in December.

“I pretty much stumbled over it… we spent some time trying to dig it up and look at it and took some photos,” Kristina Davidson told Nine News of the moment her family laid eyes on the relic.

“There’s the spine, there’s rib bones, it’s just kind of all there.”