The first day of Sanja Matsuri can fall in Sensō-ji, Tokyo
The first day of Sanja Matsuri can fall in Sensō-ji, Tokyo is held on May 16. Celebrated on the third weekend of May. This event in the second decade of the month May is annual. 
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The three men became known as “Sanja-sama” (Takenari and Hamanari Hinokuma – and their friend, Matsuchi Hajino who founded Senso-ji Temple), and the festival became known as Sanja Matsuri in their honor. It is also believed that a festival was held from 1312 in honor of the Sanja-sama, but this only took place every other year in March until 1649.
Every year huge numbers of people attend the Sanja Matsuri (三社祭), one of the three great Shinto festivals in Tokyo held annually for 3 days on the third weekend of May in Asakusa Shrine.
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Japan Day in Düsseldorf on May 29 (Celebrated on the last Saturday of May);
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