The Fujisakigu Reitaisai, Kumamoto’s biggest festival, reaches its peak tomorrow with the main parade (zuibyo gyoretsu). Here’s a link to a pdf that shows the route and also lists the times (though only in Japanese):
http://www.fujisakigu.or.jp/reisai/images/201608281537.pdf
The parade starts at 6 AM, traveling from Fujisakigu Shrine to a point near the Fujisakidai Baseball Stadium. After a rest, the revellers retrace their steps beginning at 2 PM. Though it makes for an early start, most people recommend viewing the morning parade because participants are fresher, more energetic, and less inebriated.
– KIrk