"We'll have to stick to the mountains."
Claire Healey posted photographs of the incident and a warning on Facebook: "To all the horsey people on my Facebook, please take note.
"On Merthyr Mawr today we hit sinking sand and nearly lost our horses, they were stuck there for well over an hour, this was on a bridle path.
Please be careful."
She thanked passers-by and the fire service for their help, adding: "Never been so scared in all my life."
