Jun 06, 2011 11:59 BST The Swedish Chamber of Commerce for the UK On Saturday 25 June, thousands of Swedes, and friends of Sweden, take to London’s Hyde Park for the thirteenth year in a row to celebrate Swedish Midsummer. The friendly pagan tradition involves the erection of a May Pole, flower wreaths, dancing as little frogs and a large Swedish picnic of pickled herring, gravad lax and meatballs.