So it breaks down like this:The National Holiday Laws, promulgated in July 1948, declared nine official holidays. Since many were concentrated in a week spanning the end of April to early May, many leisure-based industries experienced spikes in their revenues. The film industry was no exception. In 1951, the film Jiyo Gakko recorded higher ticket sales during this holiday-filled week than any other time in the year. This prompted the managing director to dub the week "Golden Week" based on the Japanese radio lingo “golden time,” which denotes the period with the highest listener ratings. Source.
April 29: Showa Day - the birthday of former Showa Emperor and used as a day of reflection. There are many parades and festivals on this day. In Iwakuni there was huge parade at the Kintai Bridge.
May 3: Constitution Day - the post-war constitution (approved by the United States at the time) was put into place in 1947. On this day there were huge fireworks all over the city. Zero was scared by the booms.
May 4: Greenery Day - dedicated the nature and the environment.
May 5: Children's Day - also called Boys Day. Families pray for their sons and hang carp streamers and display samurai dolls.
Many people will take the days in between off and make a whole week and take vacation. Government buildings and banks are all closed during Golden Week. Interesting how a whole country operates when everyone takes vacation at the same time!