The reason why a young woman plunged to her death on the Horseshoe Pass, near Llangollen, remains a mystery after an inquest into the incident.

Though 24-year-old Cassandra Jayne Dulson had been suffering from depression she was looking forward to returning to work and engaging well with mental health professionals, the inquest heard.

Nicola Jones, assistant coroner for North Wales East and Central, said at the hearing in Ruthin: “It is a case where there are more gaps than there is evidence.”

She recorded a narrative conclusion on Miss Dulson, of Gorse Close, Ruabon, who suffered multiple injuries when her Vauxhall Corsa plunged 80 metres down a steep slope on September 5 last year.

The red car was spotted by two quarry workers who then found her body nearby. She was thrown out of the vehicle even though she had apparently been wearing a seatbelt.

A post-mortem examination also revealed that she had no alcohol and only a therapeutic level of anti-depressant medication in her system.

Dr Rajvunder Sambhi, consultant psychiatrist with the Wrexham-based home treatment team, said Miss Dulson, known as Cassie, had been suffering since 2015 with depression.

She had suffered with psychotic episodes, but she had developed an insight into her problem and had engaged well with her acute support team.

Dr Sambhi said: “She was compliant and honest.”

Miss Dulson, who studied TV and film production at Edge Hill University in Ormskirk, had been off work for a couple of weeks before her death and Dr Sambhi said her condition had deteriorated over five to six days. As a result she was visited every day.

Mental health nurse Laura Richards told the inquest that although Miss Dulson lacked motivation, had low energy levels and admitted having had suicidal thoughts she had shown no signs of acting on such thoughts.

Miss Richards told the hearing: “There did not appear to be any imminent risk.

“I felt very privileged to have been working with her.”

David Yelland, who had recently moved to live on the Horseshoe Pass, told police it was extremely foggy the previous evening and on the morning of September 5.

At about 4am Mr Yelland was awakened by a loud revving noise.

His wife Lesley Yelland estimated the visibility at one stage to have been only five to six metres.

She also pointed out that sheep sometimes slept in the middle of the road.

No mechanical defects were found on the Corsa and collision investigator Gordon Saynor told the inquest that five seconds before the impact Miss Dulson had been travelling at 68mph, which he said was “inappropriate”.

The accelerator had been 98 per cent depressed and there were no signs of braking or swerving.

He said: “The exact reason why she left the road cannot be established.”

The assistant coroner said it would be wrong to speculate that Miss Dulson had committed suicide as the fog could have been a factor.

She added: “The consistent theme is that she wanted to get better.”