How would you like to spend a fun Sunday partying on a grave surrounded by hundreds of other tombs in a huge cemetery? Well, if you happen to be in Okinawa in April, shortly after the vernal equinox, you'll find thousands of families doing just that in high-spirited family outings at the festival time known as Shimi.

Okinawa, formerly the Kingdom of the Ryukyus, was annexed by Meiji Era Japan in 1879. During the previous 500 years, the kingdom had maintained close ties with China, and to this day much of the culture displays a strong Chinese influence. This includes Chinese cooking and clothing, dragon-boat racing and, perhaps most importantly, the lunar calendar and the 12 signs of the Chinese zodiac.

Many Okinawan birthday celebrations are tied to that zodiac's 12-year cycle, beginning with the 13th (12+1) birthday and — since Okinawans have the world's longest life expectancy and the islands have the highest population percentage of centenarians — reaching a climax with the 97th (12x8+1).