A couple has recovered the oldest-known message in a bottle from a beach on Australia’s west coast, some 130 years after a German sailor threw it into the Indian Ocean.

Tonya Illman found the bottle in the dunes of Western Australia, during an off-roading session with a friend. Illman says the pair got out of their four-wheel drive vehicle to take a walk among the dunes when they noticed a great deal of garbage in the area.

“I decided I’d simply just pick up a couple of pieces of the rubbish and take it home and throw it away,” Illman told CTV News Channel on Tuesday. “And I bent down and I picked up that bottle.”

Illman immediately noticed that there was something peculiar inside the green glass bottle, so she brought it home to examine it with her husband, Kym. They opened the bottle to find a tightly wrapped, slightly damp note inside, sealed with a piece of string.

Kym Illman says he tried to unroll the note but stopped when he tore the corner. “We thought, don’t wreck it any further. Let’s dry it out,” he told CTV News Channel.

The couple put the note in the oven on low heat for approximately five minutes, then took it out, removed the string and carefully unrolled the mysterious message.

What they found was not a love note or an S.O.S. to the world. Instead, it was a German researcher’s note documenting exactly when and where the message was dispatched, and explaining that it was dispatched in an effort to study ocean currents.

“It had an instruction to take the note and give it back to the Deutsche Seewarte in Hamburg… or the nearest German embassy,” Kym Illman said. The Deutsche Seewarte was the German Naval Observatory, which is known to have dispatched hundreds of bottles as part of a study from 1864 to 1933. More than 600 of those messages have been recovered to date, but this is the first bottle found intact.

The note indicated that this particular bottle was thrown overboard from the German ship Paula on June 12, 1886, during a voyage from Cardiff in the U.K. to Makassar in Indonesia. Researchers working with the Western Australia Museum say the bottle likely washed ashore in Australia approximately one year after it was dispatched from its origin point, some 950 kilometres away.

The Illmans say the area where they found it has been largely deserted until recently, when a new road opened it up to off-road enthusiasts.

“It was found way out in the middle of nowhere,” Kym Illman said. He suspects the bottle must have been under the sand for over a century, but was likely unearthed during a major storm that hit just prior to its discovery.

“Perhaps that’s washed away some of the sand,” he said.

The Illmans were dubious about the note’s authenticity at first, but German authorities and the Western Australia Museum have confirmed that it’s real.

The couple handed a copy of the note over to the German consul, but the original note and the bottle will be staying at the Western Australia Museum, where it will be on display for the next two years.

“It’s quite a beautiful piece and there’s no point in putting it in storage,” Tonya Illman said of the bottle. “I think it needs to be left on display and seen.”