Qing Ming Festival

from the Economist.com Cities Guide: Singapore
though this is throughout asia.

April 4th 2005

"Ancestor veneration is a Chinese tradition, and Qing Ming (“clear and bright”) is the year's most important day for it. The public holiday is also known as “Grave-Sweeping Day” or “Spring Remembrance” (there is a similar festival in autumn). Traditionally, Chinese families visit their ancestors' graves to show respect by cleaning the gravestones, clearing away weeds and touching up the surrounding area. They also decorate the graves with flowers, light incense and make offerings of fruit (usually oranges) and rice wine. Expect public transport to be crowded on this day, and if your journey takes you near any cemeteries, expect traffic jams.

In the early hours of April 4th, the temples of Chinatown will fill up with families burning candles and incense. To soak up the atmosphere, visit Kong Meng San Phor Kark See Temple on Sin Ming Road."