Tomb Sweeping Day, also known as "Ching Ming" Day or Ancestor Worship Day, is an important traditional and national holiday which is celebrated to show respect for ancestors and filial piety. Unusually, this is one of the few Chinese holidays to follow the solar calendar and usually takes place on April 4, 5 or 6.
This spring festival's Chinese name means "clear and bright" (Ching Ming) and is marked by most residents with an outing into the countryside or back to hometowns to clean up family tombs. Offerings of food and paper "spirit money" are also made to ancestors' spirits. This outing frequently turns into an enjoyable family picnic-style outing, but can also mean heavily congested highways for those traveling any distance.