The disembodied laughter of children and a mysterious woman in blue.
Thousands of people tour the Port Arthur Historic Site every year and many of them report creepily similar experiences.
Port Arthur has a long history. It began in 1830 as a timber station, and for the next twenty years it housed some of the most hardened criminals from England, along with petty convicts and repeat offenders from other prisons around Australia.
It also housed the families of convicts - many of them young children.
The harsh living conditions and the manual labour these convicts undertook, meant they often died young and under horrible circumstances, and many believe they haunt the historic site to this day.
When Stateline Tasmania visited the site in 2003, the Port Arthur Ghost Tour guides showed them through thousands of written reports by people who had experienced something paranormal while on the tour - and they all had eerily similar stories to tell.
Many reported seeing a 'Blue Lady' who some believe is the ghost of a woman who was married to a Port Arthur accountant. The couple apparently lived in the penal colony during the 1800s.
"I saw the figure of a lady in a crinoline dress and a bonnet with arm outstretched."
"The woman had a pale dress from waist to ground."
"Figure of a youngish woman wearing a long blue/grey dress looking out of a back door of the building."
Legend is the woman and her baby died during childbirth and so she keeps returning to that particular building day after day, looking for her unborn child.
Others have reported seeing a little girl who has fallen down the stairs at the commandant's house.
"I felt a little girl laying at the bottom of the stairs," one person said. "She was laying in a pool of blood. Her right arm is broken. She is really scared."
"I could hear the little girl as I walked up the path."
"Her arm is twisted up under her. I felt like my arm was hers."
While many tourists are haunted by the sound of children laughing and playing.
The children run up and down the stairs, playing and laughing, and on balmy, still summer nights you can hear them playing hopscotch and singing skipping songs.
In 2015 a visitor captured some ghostly apparitions on camera during the tour and posted them to the Facebook page 'Australian Hauntings'. One photo shows the figure of a small boy lurking in one of the cells, while in another photo a ghostly white smudge.
But possibly the most spine-tingling image is that of several ghostly, child-like figures peering out the windows of one of the buildings.
Whether or not you believe the legends of Port Arthur, its long history and haunting architecture, are enough to make your spine tingle.