Hundreds of thousands of people are expected in Amsterdam for the traditional Koninginnedag or Queensday holiday festivities marking the birthday of Queen Juliana, mother of the reigning Dutch monarch, Queen Beatrix of the Royal House of Orange, on 30 April. Amsterdam puts on a huge open-air party for the occasion, celebrated annually since 1909, with citizens dressed in orange and musicians and impromptu stalls selling everything from beer to handcrafts on every street corner. According to Holland-based tourist agency only two per cent of hotel beds in the city are still available for booking over the holiday period.