Traffic was brought to a standstill on Monday morning after a lorry jackknifed and crashed through the central reservation of the M4 near Bristol.
The crash caused 15 mile tailbacks in both directions, as the lorry obstructed both carriageways.
Highways England said it was one of three accidents on the motorway between junction 14 and junction 20, which caused traffic to back up into Wales.
Photographs released by Highways England showed the vehicle after it collided with another lorry on the westbound route around 6am.
The lorry blocked two lanes on the eastbound side of the M4, while a large shipping container which fell off the back blocked two lanes on the westbound side.
Emergency services were working to clear the wreckage but traffic was still slow many hours after the crash.
Motorists were told to expect a wait of up to one hour and 40 minutes on the M4 and advised to take alternative routes.
There were two other crashes on the motorway on Monday morning, which further contributed to the delays.
At around 7.30am, two vehicles collided at junction 20 for the Almondsbury Interchange and another crash closed two lanes between junction 15 and 14 eastbound near Swindon just after 9am.
