If you missed out on Thailand’s annual vegetarian festival this year, don’t worry because you have another chance to catch it at the end of this month. Vegetarians in Thailand have an extra reason to celebrate this year, as 2014 is scheduled for a double dose of the yearly vegetarian food feast.

If you’re in Thailand this year, consider yourself extremely lucky—the double festival only occurs once every 180 years. Much like sighting a rare comet, it’s something you’ll only experience once in your lifetime.

The reason for the double festival is due to the difference between the traditional Chinese lunar calendar and the solar calendar. Since 12 lunar months of 29-30 days each add up to slightly less than a full 365 day year, the lunar calendar has to add a 13th month every so often to keep the months lined up with the seasons. The extra month

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