According to Wikipedia: "The Qingming or Ching Ming Festival, also known as Tomb-Sweeping Day in English, is a traditional Chinese festival on the first day of the fifth solar term of the traditional Chinese lunisolar calendar. This makes it the 15th day after the Spring Equinox, either 4 or 5 April in a given year. ...
"Qingming has been regularly observed as a statutory public holiday in China. In Taiwan, the public holiday is now always observed on 5 April to honor the death of Chiang Kai-shek on that day in 1975. It became a public holiday in mainland China in 2008."
My diary says it's celebrated in Taiwan on the 4th April, but Wikipedia is probably right about it being the 5th.
I know it's unworthy of me, but I can't help but imagine a "bizarro-world" in which the festival of Tomb-Messing Day is celebrated. On that day, everyone has to go to the nearest tomb and mess it up -- throw garbage at it, or dead leaves, or evil sandwiches. It's also known as "Disrespecting Your Ancestors Day".