"When you're homeless, people don't look at you. They look through you," the founder of the Invisible Cities initiative, Zakia Moulaoui Guery, told AFP.
Sonny Murray, 45, knows this only too well. He came to Invisible Cities after a spell being constantly in and out of prison.
"It was brutal, to be honest. Because I was addicted to drugs and stuff," he said.
"I was shoplifting ... when I wasn't in prison, I was coming back out and I was homeless on the streets, just like a revolving door," he said.
Now as Invisible Cities' lead tour guide he trains others, helping them to turn their life around just as he did.
All the tours are unique and devised by the guide themselves, he said.
Murray's tour, which starts at the site of a former gallows, focuses on crime and punishment.
One of the highlights of his itinerary, however, is the Edinburgh Support Hub run by Scotland's leading homeless charity, The Simon Community.
When he was homeless, it was "literally the only place in Edinburgh where homeless people could come and have a shower or wash their clothes and stuff," he said.
"It's a horrible feeling going about and not being able to have a shower and wash your clothes and that after a couple of days. So I used to come here all the time," he added.
'Positive environment'
Homelessness is on the rise in Scotland, with an eight percent rise this year in those either assessed as homeless, who were in temporary accommodation or had made homelessness applications.
French-born Moulaoui Guery said she hoped Invisible Cities' work was helping to tackle the sense of being unseen experienced by homeless people.
"All of a sudden, to empower people to be visible and the centre of attention and lead a tour, I think that's really, really important," she said.
There are currently 18 guides helping visitors discover aspects of the city they would not normally encounter.
Similar tours are also run in a number of other UK cities, including Glasgow, Manchester, Cardiff and Liverpool.
Moulaoui Guery, who set up the initiative in 2016, said it was good for tourists to get a chance to scratch beneath the city's picture-postcard surface.
"You can talk about the castle and Victoria Street and Harry Potter and all the different things that make it magical, but you can also talk about real topics," she said.
With a lack of support networks and relationship breakdown among the leading causes of homelessness, Invisible Cities tries to "recreate community and a positive environment", she said.
"It's about training more people and having the current guides move on so we can create more opportunities for others to become guides," she added.
So far, around 130 people have undergone the training which aims to act as a stepping stone to other training or employment opportunities.
But Murray said the benefits were not a one-way street.
Tourists benefit from a broader view of the place they were visiting, he said.
Not only that, he added, it also offered them the satisfaction that they were helping the city's "homeless down the line".
