A woman who mysteriously vanished three weeks ago made a booking at a backpacker hostel the morning she disappeared – but never returned to stay the night.
Kathleen Riethmuller was last seen on security camera footage visiting shops in Sydney’s north on October 28.
Hours later, the 28-year-old’s belongings including her ID, phone and bank cards were found abandoned in a backpack in a suburban street at Lane Cove.
Her family hasn’t heard from her since and police have launched a nationwide hunt.
A family friend, who wished to remain anonymous, has revealed new details about her last known movements – as her family plead for anyone with information to come forward.
Kathleen Riethmuller, 28, (pictured) has been missing for three weeks since she mysteriously vanished from Sydney’s northern suburbs
The friend said police have determined she checked into Elephant Backpackers, in Woolloomooloo, on the morning of October 28 – just hours before her last sighting.
Staff reported that Ms Riethmuller seemed ‘jittery’ and abruptly left after signing in.
‘She went into the backpackers and made booking for that night but didn’t stay,’ the friend, who speaks on behalf of Ms Riethmuller’s father, told Daily Mail Australia.
‘She didn’t go into the room – just made the booking and left.’
The friend said Ms Riethmuller’s Brisbane-based family, who can’t travel to Sydney due to Queensland’s Covid restrictions, are distraught by the business graduate’s unusual disappearance.
Although dropping out of contact is out of character for Ms Riethmuller, her family were at first hopeful she had chosen to retreat – but their concerns continue to grow with each passing day she is not seen.
‘Her family are very devastated and a bit at ends because there are not any leads to go off at the moment,’ the friend said.
‘A lot of information has come through to police but there have been no verified sightings of Kathleen since the day she went missing.
Police inquiries revealed Kathleen attended a retail store on Reserve Road, Artarmon, about 11.40am on Thursday 28 October (pictured, left), before she was spotted again at 2.30pm the same day in North Sydney, wearing a long sleeve denim dress and black flat shoes (right)
A family friend has told Daily Mail Australia a ‘jittery’ Ms Riethmuller checked into Elephant Backpacker (pictured) in, Woolloomooloo, the morning she disappeared
A member of the public later found her belongings, including her ID and bank cards, in a backpack on Centennial Avenue (pictured) at Lane Cove
‘The situation is bewildering. Her family is very confused and really just want to get her back.’
While she was in regular contact with her family, Ms Riethmuller was very private – offering them very few details about her friendship circles or life in Sydney since she moved to the city around five years ago.
Her loved ones believe she may have been in between houses at the time of her disappearance and it remains unclear whether or not she was working.
Adding to the mystery, Ms Riethmuller tried to sell a list of possessions on Gumtree in the days before she vanished, with police exploring the possibility she travelled to Melbourne for work opportunities.
However, vital documents needed to start over in a new city – like her ID- are sitting unclaimed in a Sydney police station.
One friend has told family Ms Riethmuller said she was considering travelling back to Brisbane, but other than that acquaintance, no one has been able to paint a picture of the ex-private school student’s life.
‘There are no close friends who have been able to give us information about the last couple of weeks leading up to her disappearance,’ the friend said.
Kathleen Riethmuller, 28, (pictured) has been missing for almost three weeks after mysteriously vanishing from Sydney’s north
The friend said little is known about Ms Riethmuller’s ‘reclusive’ life in Sydney over the past few years. She is pictured in a Facebook post from May
‘There are so many gaps. Did she have a partner? Why was she moving out? They are all questions no one knows.’
The family are pleading for anyone who has information about Ms Riethmuller to come forward to help piece together where she might be.
If Ms Riethmuller is somewhere safe and well, her father asks: ‘Please come home safely or to get into contact. Just let someone know you’re ok.’
After checking into the backpacker hostel, Ms Riethmuller attended a Bunnings store on Reserve Road, Artarmon, about 11.40am on Thursday 28 October.
She was spotted again at 2.30pm the same day in North Sydney, wearing a long sleeve denim dress and black flat shoes.
Her backpack was found by a member of the public later that afternoon on Centennial Avenue, Lane Cove, sparking the investigation into her whereabouts.
NSW Police first issued a public appeal for help finding Ms Riethmuller on October 31, which was renewed two weeks later as leads ran cold.
Detectives have now extended the search into Victoria as they explore the suggestion Ms Riethmuller may have travelled to Melbourne.
Family are pleading for Ms Riethmuller to come home or let someone know she is safe
A map posted in a Facebook page dedicated to finding Ms Riethmuller shows her known movements around Sydney around the time she disappeared
It is understood police remain open-minded to all possible causes of Ms Riethmuller’s disappearance and are following all lines of inquiry.
Aside from the hostel, she was also known to have frequented a unit on King Street in the weeks leading up to her disappearance.
Ms Riethmuller graduated from Brisbane Girls Grammar – which costs about $26,555-a-year – in 2010 before studying a Bachelor of Business Management/ Science at The University of Queensland, according to her social media profiles.
In one of her Instagram accounts, Ms Riethmuller said she worked in ‘data science, innovation and market developments’ with ‘experience in consulting, finance and start-ups’.
She frequently posted on photos of work conferences and new technology projects she was apart of on the professional social media profile between 2017 to 2019, when the account appears to have become inactive.
The new details about her disappearance come after Daily Mail Australia revealed Ms Riethmuller had posted 11 items for sale on Gumtree between October 16 and 22, with a collective value of $1,260.
The goods include a $350 hand mirror, $200 pull up/tricep dip frame, $150 wall tapestry, and a $100 vintage 70s style room divider.
Ms Riethmuller’s (pictured) phone, ID, bank cards, and other belongings were found abandoned in a suburban street on the day she was last seen
In the week leading up to her disappearance, the 28-year-old listed several items for sale on Gumtree (pictured, left and right)
None of the items have been marked as sold and there has been no activity on the Gumtree account since she vanished.
A Facebook page dedicated to finding Ms Riethmuller has now been launched to help in the hunt.
Family fear she may need medical assistance, and have shared a map of her last known locations, urging anyone with information to come forward.
‘We ask that those with dash cameras who were in the vicinity of any of the below areas during or around the hours of 11am – nightfall have a look to see if they can spot Kathleen or anything else that could help locate her,’ begs the page.
‘We are hopeful that reaching out as far and wide as possible can assist in getting her home safely.’
Ms Riethmuller is described as Caucasian, about 165cm – 175cm tall, with a thin build and long dark hair.
Anyone who may have information about her whereabouts or has seen her is urged to contact Chatswood Police Station or Crime Stoppers on 1800 333 000.