The festival took place for the first time in 869; it was a religious ceremony to prevent plagues and natural disasters. Nowadays, the festival of Yasaka shrine in Kyoto, Gion Matsuri, is probably the best known Japanese festival. It lasts the whole month of July, so come enjoy it!
The main event is on the 17th with the YAMABOKO PARADE:
“The world Yamaboko refers to the two types of floats used in the procession: the 23 yama and 10 hoko. One of the reasons the Gion Matsuri is so impressive is the enormity of the hoko, which are up to 25 meters tall, weigh up to 12 tons, and pulled on wheels as big as people.”
http://www.japan-guide.com/e/e3942.html
On the 14th to the 17th of July, at night, you will be able to attend the YOIYAMA festival: floats are put on display, within a festive atmosphere, traditional music and street hawkers.
On the 16th, at night, every traditional district is illuminated with lanterns, hangings and floral banners.
Sources:
http://www.japan-guide.com/e/e3942.html
http://www.matsuritimes.com/gion-matsuri-yamaboko-parade/
http://www.nippon.com/fr/views/b03301/
