The Thai Vegetarian Festival, also known as the Nine Emperor Gods Festival, is a nine-day celebration that occurs on the eve of the ninth month of the Chinese lunar calendar. The festival is celebrated throughout Thailand by people both with and without Chinese ancestry, with the largest celebrations taking place in Phuket. The festival feels more carnival than convent, and is a lively, thunderous, surreal celebration.

Even though Vegetarian is in the title of the festival, it’s actually a vegan festival and food is prepared both without the traditional meats, but also all animal products — which includes eggs, dairy, honey, fish sauce, oyster sauce, and shrimp paste. Some even leave out particularly strong ingredients like garlic and onion. It leaves a very flavorful cuisine a bit more bland for these days when participants intend to cleanse their body, mind, and spirits.

Look for bright yellow flags with two red symbols (เจ) slashed across them hung from food stalls and restaurant facades. The word is pronounced jay, and signifies vegetarian cuisine. But the principle of jay isn’t limited to diet; those practicing jay wear white, agree to keep their body clean, keep up a high moral standard in action, words, and thoughts, and abstain from sex and alcohol.

But don’t expect the vegan cuisine to be your biggest takeaway from the event; the image that’ll be burned in your brain will probably be the people piercing their faces with swords.

Although the festival is Chinese in origin, the Thai people have their own extraordinary religious rituals that, to be honest, might turn your stomach. Participants acting as masong (mediums for the gods) enter a trance state and undergo ritualized mutilation that includes impaling their skin — from cheeks, arms, and faces to legs, backs, and tongues — with objects of varying size. Everything from needles and machetes to handguns and bull horns are used. Other practices include slashing their tongues with swords and knives, climbing ladders made of blades, firewalking, and standing up close to exploding fireworks.

It’s believed that while the masong are possessed, they won’t feel any pain. What’s amazing is that scarring and stitches are uncommon, and most return to work shortly after they complete their ritual. Tourists are invited to attend the festival, take part in the processions, and snap photos. But even if it appears to be an insane festival to the outsider, it is a deeply religious celebration to the Thai Chinese people so, as always, be respectful.

The 2018 Thai Vegetarian Festival will take place from October 8th to 17th. All Chinese shrines in Phuket participate in the festival, but if you want to see bigger celebrations, make sure you visit the major shrines (which include the five oldest). Events move around the city, check here for a calendar of events.