The bush itself is unremarkable: a mess of brambles and leaves measuring roughly three metres across in the middle of nowhere.

At its base is a makeshift shrine of recycled bottles and a metal case containing a guestbook, a handwritten brochure and black biro.

For almost 120 years, strangers connected by nothing more than the tragic story behind the bush have come from as far as Kenya and Alaska to water it.

The bush — an unruly bougainvillea — was planted in 1902 in Siberia, now a ghost town in Western Australia, as a memorial to an infant boy who died soon after birth.

"The little bub's memory will linger on," reads a message scrawled in the guestbook from 2004.

Another reads: "Sleep well little baby".

The boy's heartbroken mother, Mabel Kirkham, planted the bush a short distance away from the cemetery where her son was buried.

The bougainvillea bush has been kept alive by hundreds of strangers over the years. ( ABC Goldfields: Andy Tyndall )

He was unnamed, and lived for only for a brief few hours, before his death from an unrecorded cause.

"This bush shall never die for my heart lies beneath it," Mrs Kirkham reportedly said at the time.

Remarkably, so far, the bush has lived on exactly as predicted.

More than a century after it was planted, it continues to thrive with the assistance of hundreds of tourists, locals and passing mine workers who stop to water it.

Driving north of Kalgoorlie, the bush is marked by a shock of purple and green ringed by a rusting fence on the side of a dirt track.

Visitors from around the world have left heartfelt messages in a guestbook beneath the bush. ( ABC Goldfields: Tom Joyner )

"It's absolutely marvellous to think it's survived through drought and even a cyclone," Maureen Pickford said.

Ms Pickford is the great-granddaughter of Mabel Kirkham, and travelled from her home in Waikerie, South Australia last year to Siberia to see the memorial for herself.

She said that when she was there, she pictured the parents with their child in her mind.

"You could see them both holding the child," Ms Pickford said.

"And as any mother would feel, I felt very emotional."

'It's a beautiful story'

Little remains of Siberia today other than a track, a cemetery and the remnants of the pub that once stood near where the bush now grows.

It was the site of an ill-fated gold rush in 1893, where an unknown number of prospectors perished in the heat without adequate water.

"[Two men] have succumbed to thirst twenty-five miles on the track," the West Australian newspaper reported in October that year.

Siberia, an hour's drive north of Kalgoorlie, has a tragic past characterised by despair and death. ( ABC Goldfields: Tom Joyner )

"Five others have been found in a state of nudity and perfectly insane from the effects of thirst."

A convoy of camels was promptly dispatched to Siberia carrying water and supplies, but for many it was too late.

The bougainvillea is one of the few reminders of a settlement there.

Only a short drive from the bush is another historical gold mining town, Ora Banda, where today only a handful of residents and a pub remain.

Publican Kiri Pomery, who took over the pub a few years ago, often points curious patrons towards Mabel Kirkham's bush.

"I find it's a beautiful story," Ms Pomery said.

"I will direct everyone out there to have a look at least once."