Lincolnshire Police have appealed for car drivers and motorcyclists to take extra care on local roads this evening (Monday).
Thousands of fans were expected to leave a major motorsport event at Cadwell Park between Louth and Horncastle.
In addition, heavy traffic was expected back from the coast as day trippers made the most of the superb Bank Holiday weather.
Potential hot- spots included the A158 \and A153 through Horncastle and the A16 Louth-bypass.
Earlier today, there were reports of lengthy tailbacks in the Cadwell Park area - and in Wragby.
Horncastle police reported traffic was also heavy in the town as vehicles headed for the coast.