Queen's Day (Dutch: Koninginnedag) on April 30 (or celebrated on April 29 if the 30th is Sunday) is a national holiday in The Netherlands. It started as a celebration of the Dutch monarchy. The holiday is celebrated on this date because it was the birthday of Queen Juliana (1909-2004). When Queen Beatrix succeeded Juliana in 1980, she decided to keep the holiday on April 30, as the weather on her own birthday, January 31, tends to prohibit the traditional outdoor festivities.
In recent years, Queen's Day has become more and more of an open air party, particularly in Amsterdam, which attracts anywhere from 500,000 to two million visitors. Of course with a little baby we can’t really join in anymore. So we just enjoyed the public holiday and the nice weather.