A tourism revival of an ancient celebration.
Originally, ceremonies were held on the day of Ghost Festival (农历七月十五日), but were later changed to July 16th to commemorate Chairman Mao swimming in the Yangzi. Most recently the festival was revived as a tourism event from August 1. See http://www.dalidaily.com/dianzi/site1/dlrb/page/1/2015-08/05/B3/20150805B3_pdf.PDF