Traditionally, women could not participate in the procession (gyoretsu) of a matsuri. They could be ritually unclean due to menstruation, or could have experienced some other kind of defilement (kegare) that would require ritual cleansing (oharae). Male participants carrying the mikoshi were always strictly monitored before the ritual, then purified by priests before its beginning.
Today, women are welcome participants in most festivals and even join in the hard work of shouldering the mikoshi. Kyoto's famous Gion matsuri allowed women in the procession as recently as 1994.
All photos and text © Copyright John K. Nelson, 1999