Each year one of the biggest radio stations in Holland organise a big party during the National Holiday Queensday! Every year on April 30th from 12:00 to 21:00 the Museumplein in Amsterdam is filled with 300.000 visitors entertained by excellent performances by many top artists. In 2011 the radio station organized this event for the eleventh time. The Radio 538 Queendays Festival at the Museumplein in Amsterdam is the largest free outdoor concert in the Netherlands.