The walls of Sheffield's Old Town Hall contain 200 years of history, from the building's days as a court to its time as the home of city democracy.
But all that is under threat unless the right developer with a combination of deep pockets and a respect for heritage comes forward.
So says Matthew Holmes, an 'urban explorer' who managed to get into the Grade II-listed building and photograph the decaying grandeur inside.
He was amazed by what he saw, from the cavernous court rooms to the white-tiled prison cells. But he also found water-damaged floors, smashed windows and graffiti.
"When you are one of the few people that has been inside, you feel like you have achieved something," said Matthew, a 22-year-old estate agent.
"Then afterwards you get a feeling of sadness, that the building is falling down. In another 10 years it won't be there."
The Old Town Hall has been up for sale for more than a decade, with little public interest from developers. Its listed status and internal design mean it would require huge investment to develop sensitively.
But according to Tim Bottrill of Fernie Greaves, the firm marketing the building, its owner G1 London Properties Ltd is considering putting in a planning application to develop the site itself.
"I think you could easily have it as a hotel," said Matthew. "You are fairly limited. But you could use it as an arts space.
"You could even have the court rooms and the prison cells as a museum."
Matthew lives in Manchester, but found out about the Old Town Hall online. He has a passion for Victorian architecture and often explores abandoned and disused buildings.
Although he is usually trespassing, he believes it is worth the risk to record the treasures hidden inside.
"When you walk into these places you never know what you are going to find," he said. "The court rooms were the biggest surprise in the Old Town Hall. The woodwork and the architecture - they just don't make buildings like this any more."
And Matthew's concern for historic buildings is based upon what he has seen in his home city.
"The problem is we have quite a large property boom in Manchester. There is not enough space for university tenants. So a lot of these buildings are being lost to people with deep pockets, and to build these monstrosity apartment blocks."
The Friends of the Old Town Hall was set up in November 2014 to campaign for the restoration and re-use of the site.
Chairman Valerie Bayliss said there had been a number of significant changes to the hall in the last six months, and Matthew's photos proved the pressing need for restoration work.
"Vandals have been in. There is graffiti on the inside of windows upstairs, and a couple of windows have been broken," she said.
"Recent photos show some quite systematic smashing of glass on individual doors and panels. That's pure vandalism.
"The clock hands have started being moved again from time to time. It's very disturbing.
"And one court is very seriously water damaged."
The friends group is aware of the owner's intention to develop the building.
"We have always had a clear view," said Valerie. "Our aim is to get that building properly and respectfully restored and back into productive use.
"We would very much prefer that it was in community hands and had a financially sustainable mixed use."
She added: "If there was a respectful restoration into a useful building for the city we would not make a fuss about it."
G1 London Properties Ltd bought the building in 2004, for a reported £650,000.