Police are appealing for witnesses to a road traffic collision which occurred near the Camelot Holiday Park on the A7 at Longtown at 6:10pm on Monday 17 July.
A heavy goods vehicle travelling towards Longtown crossed onto the opposite side of the road, leaving the carriageway and colliding with a hedge.
A spokesman for Cumbria Police said: “The 48-year-old driver is believed to have suffered a medical episode and was found unresponsive.
“He was taken to the Cumberland Infirmary, Carlisle where he sadly past away.”
A spokesman for Cumbria Fire and Rescue Service said: “At 18:15 firefighters were called to a road traffic collision with a person who was trapped on the A7, Sandysike, Longtown.
“Three fire engines, one from Longtown, one from Carlisle West and one from Penrith, attended the incident.
“One casualty was extracted from a vehicle and handed into the care of the paramedics.
“Firefighters were at the scene for an hour.”
The road was closed for four hours to allow for recovery of the vehicle.
No other vehicles were involved.
Police are appealing for any witnesses to contact Cumbria Police via 101.