Held this year on April 6, the festival is a celebration of the penis and fertility. People parade gigantic phallic-shaped mikoshi (portable Shinto.
The Shinto Kanamara Matsuri is held each spring at the Kanayama Shrine (金山 神社, The Kanamara Matsuri is centered on a local penis-venerating shrine. A day at the Kanamara Matsuri in Yamasaki · The shrine's festival webpage.
16 Jaw-Dropping Pictures From Inside Japan's Penis Festival make it to Kawasaki from Tokyo in an easy day trip on the first Sunday of April.