A tractor was left teetering on the edge of a 140ft-high bridge after a three-vehicle crash near Chirk in Wrexham.
Farmer Joe Wilson, 23, was driving and his brother Ben, 26, was a passenger when the front wheel of the tractor smashed through the barrier at the side of the bridge on Monday.
The crash also involved a Ford Fiesta and a Vauxhall Corsa.
Speaking to the Mirror, Ben said they were lucky to be alive: "We could have been killed quite easily. We're just thankful to be still be here today. Our family feel grateful that we never went over the edge."
The pair were heading to Oswestry at the time of the crash. A picture of the tractor's wheel teetering over the edge of the bridge was taken by a member of public and uploaded to Twitter.
The Welsh Ambulance Service attended the scene and said a woman, a driver of one of the cars, was taken to hospital after the crash.
According to the Telegraph, a spokesman said: "We responded with a rapid response vehicle and an emergency ambulance and a woman in her 30s was taken to Wrexham Maelor Hospital.
A West Midlands Ambulance Service said another person was taken to hospital with minor injuries, while a North Wales Fire and Rescue spokesman said one person had been cut free from a vehicle after the crash.
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