The M20 is expected to reopen on Sunday after a footbridge crashed on to the carriageways, sparking hours of traffic chaos on one of the busiest weekends of the year.
The bridge came down between junctions three and four shortly after noon on Saturday when a digger being transported on the back of a lorry collided with it.
A motorcyclist in his 50s was taken to hospital in Tunbridge Wells with suspected broken ribs following the incident and the driver of the lorry was treated for shock at the scene.
A major incident was declared on the main route to the Channel Tunnel and the Port of Dover, with images on social media showing remains of the footbridge and damaged vehicles on the carriageway.
Alex Magaisa was driving past the lorry involved just as the bridge collapsed, with his wife and two young sons in the car. They were on their way to Gatwick Airport to catch a flight to Belfast to see family for the bank holiday weekend.
The University of Kent lecturer, 41, said: "My instinct was just to drive through. My wife saw the bridge falling and there was a big noise. I had to manoeuvre through the debris.
"We stopped afterwards for about 30 minutes, and there was another car with a family behind us. Luckily no-one seemed to have been hurt.
"It was a big shock. It's only just starting to sink in now what might have happened. We were right in the line of fire and we could have been crushed."
Highways England said that the part of the M20 between junctions two and four will remain closed until at least noon on Sunday, with crews working through the night to clean up the scene.
The adjoining M26, which was closed eastbound between the M25 junction 25 and the M20 J3 to "assist management of traffic" following the incident, is also likely to stay closed until the area is completely cleared.
Andy Sunnucks, 24, who also saw the incident, said: "We were about 15 cars back on the same carriageway as the collision.
"It looked like a lorry had jackknifed, and I could see half the bridge was missing. We went to have a look and the back end of the lorry was in pieces."
The graphic designer, a passenger travelling from Maidstone to Sevenoaks, said: "The motorcyclist was laying down underneath his bike."
An estimated 13 million drivers are expected to take to the road for a holiday or an outing between Friday and Monday, according to the AA.
Saturday was expected to be the busiest single day for motorists embarking on leisure journeys, with 10 million drivers predicted to be getting behind the wheel.