Blackpool may be one of England's most famous seaside resorts - but Liverpool was one of the first, university archivists have said.
Historical film footage, diaries, maps and poems from the past three centuries have been scoured by experts to plot the development of holidays.
They found references to sea bathing in the diaries of city residents dating back to the 1730s.
The University of Liverpool presented the findings at an event in Southport.
Its centre for archive studies said the event, which happened on Saturday, showed how people have used their leisure time since the 1700s.
Allan Brodie, from English Heritage, made the discovery about early sea bathing in Liverpool.
He said: "I have found descriptions of 'bathing wagons' in diaries of Liverpool people which date back to the 1730s, as well as references to organised visits to Crosby for sea bathing.
"Liverpool was at the forefront of providing seawater baths around this time."