The riddle of the final resting place of Western Australia’s first bishop has finally been solved.

While it has long been known he was buried beneath St Francis Xavier Cathedral in Geraldton, an archaeological dig during renovations has revealed the exact position.

Bishop William Bernard Kelly was born on a boat from Ireland to Australia in 1854 .

When he died in 1921, his body was brought to Geraldton, where he had been its first bishop.

He was buried beneath the foundations of the cathedral which was under construction but the exact location had not been marked.

His final resting place was vaguely described as “behind the throne”, but no one recorded where the throne was when it was later removed some years ago.

Father Robert Cross is an archaeologist specialising in the cultural heritage of the church.

He has now exhumed eight “lost” bishops.

William Bernard Kelly was born on a boat sailing to Australia from Ireland. Photo: Father Robert Cross/ABC

“The same happened in Perth, accurate records weren’t kept so archaeology was the way to approach it, and archaeology led us to him,” he said.

A cutting deep into the floor revealed a brick vault which held the bishop’s coffin of timber and lead with a glass panel.

“As we looked into the coffin we could see there that there was a skull so to confirm it was Bishop Kelly I decided to open the coffin and exhume the body,” he said.

“He was vested in priestly vestments that basically consisted of a green chasuble, which is the outer vestment that a priest or a bishop wears when he’s celebrating a mass.

“Underneath that he was wearing what looked like a red cassock, and red is always associated with a bishop so we knew at that time that this was certainly Bishop Kelly.”

The green chasuble is a nod to his Irish heritage but not strictly according to Roman ritual.

“I guess it expressed the fact that we’re in a country diocese here, far from Rome and perhaps Roman protocols aren’t always followed to the letter of the law,” Father Cross said.

Bishop Kelly’s remains will be reburied once the cathedral renovations are complete and his final resting site will be properly recognised.

-ABC