Bannockburn Riding for the Disabled Association near Stirling - a national centre for excellence - has told clients it had closed for safety reasons after its access road became unpassable.
The charity has been at its home on Sauchieburn estate, near Kippen, for nearly 20 years but has been in a dispute over repairs to the road with its landowner Bill Roddie.
Until this week it had been able to continue providing life-enhancing riding experiences to 200 people a week using its stable of 17 horses.
However, the charity's management has now issued a statement saying it is now longer safe to stay open.
In an email to clients, it said: "The group has been attempting to resolve issues surrounding repair of the access road with its landlord for some time now.
"Bannockburn RDA staff recently made temporary repairs to the road to enable users to continue to access our services.
"Within a few days estate workers employed by the landlord removed the temporary repairs and in the process made the pothole situation worse.
"As a result Bannockburn Riding for the Disabled was forced to close on the grounds of safety.
"Taxi and minibus drivers refuse to use the road to bring disabled clients to the centre.
"This dispute has plunged the centre into crisis as without income it will be unable to operate.
"We are appealing to everyone who knows about the work of the centre to support us as we try to find a resolution to this situation."
The Bannockburn centre, which has its own stables, cafe and viewing balcony, employs eight people and has another five on government work placement schemes. It costs just £200,000 just a year to run.
It was set up thanks to the generosity of the estate's previous owner, Guy Stafford, who invested in turning an old cowshed in to what is now one of the most important centres of its kind in Scotland.
Mr Stafford died in 2006 and the estate was bought by Mr Roddie, a property developer with a conviction for fraud.
By 2008 Mr Roddie was at the centre of a "right-to-roam" row over the estate after putting up 6ft high fences and gates that effectively blocked access to a local beauty spot.
Walkers, backed by the Ramblers' Association, complained and Stirling Council ordered him to remove the fences, which had been topped by screws and anti-climb paint
Most of the 7000-acre is wooded but it includes Mr Roddie's home, in the Scots baronial style, a small lochan and a riding school. When challenged about his fences back in 2008, the entrepreneur refused to comment.
One regular user of the riding centre said clients were devastated.
"I'm appalled to hear about the enforced closure of the centre," she said. "This is a really special place. The staff are experts. They help adults and children right across the spectrum of physical disabilities and learning difficulties.
"I've been going for two years and the benefits for me, both physically and mentally, have been huge."
"I've seen blind people beaming with delight when they get on a horse and children with severe cerebral palsy become able to relax their bodies and control the ponies by themselves.
"You can't underestimate the impact of the work this charity does."
The Herald sought to contact Mr Roddie through his company Spectrum Properties but he failed to respond.