Motorists are experiencing heavy traffic for the third day running ahead of Ed Sheeran's latest Cardiff show.
The pop star played the last of three sold-out shows at the Principality Stadium on Saturday night.
Long delays and queues were reported again on the M4 westbound between the Prince of Wales Bridge and J26.
Rock group My Chemical Romance were also playing in Cardiff on Saturday, further contributing to traffic problems.
Coach operator Megabus apologised to customers after its 13:50 service from Cardiff to London was delayed by an hour, due to congestion.
There was further travel disruption in the capital after a woman was hit by a bus in the city centre.
Emergency services attended the incident, which occurred outside the Queen Street Sainsbury's store.
Police later confirmed that the woman had died.
SERVICE UPDATE: We’re sorry that the 13:50 service from Cardiff to London is delayed by around 60 minutes due to traffic congestion in Cardiff.— megabusUK (@megabusuk) May 28, 2022
Here are the stops affected:
London 28:05#MegabusUpdates pic.twitter.com/0MwYhxZOnP