These photographs are from Gaynor Williams. The postcards at the top are from early 1930s and depict an unusually large crowd at the promenade’s Open-Air Bathing Pool (or 'The Baths' if you like). The event may have been the opening day in 1930. Swimming outdoors in unheated water was not the only self-inflicted punishment on offer; the other photos show a Keep Fit class there, the lower picture is a detail of the one above.
Love those costumes.
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SAT 25th NOV 2017 UPDATE: Also staged there - exhibition diving. The following card postmarked 1956 captures one such event nicely.
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