Motorists have been warned of 'severe delays' through the county as festival-goers return from Latitude Festival.
Traffic is moving at an average speed of 15mph on the A12 southbound following the three-day festival at Henham Park in Southwold.
There is "heavy traffic" on the A145 and delays are expected throughout the day as attendees leave the site.
In terms of public transport, extra staff have been added on the Greater Anglia lines to support revellers returning from the festival.
In a tweet, Greater Anglia News said: "If you're travelling home from @LatitudeFest today, we will have extra staff on hand to help you."
More than 40,000 people flocked to Henham Park over the weekend to enjoy various music, theatre, arts and comedy from across the world.
Festival director Melvin Benns said: "Latitude 2019 has passed all my expectations.
"I am delighted that this year has been this biggest Latitude in history," he said.
Keep up to date with the latest delays by viewing our Live Traffic Map.
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