Under the skin: Thailand's tattoo festival

Thailand is notorious for its range of arcane festivals. But one of the strangest is the tattoo honouring ceremony held each March at Wat Bang Phra temple about 50 miles west of Bangkok near the town of Nakhon Chai Si Photograph: Andrew Spooner

Like Phuket's Vegetarian Festival, with its mass piercings, and the Bun Bang Fai rocket festival, where thousands of fireworks explode into the sky in a giant fertility rite, it is linked to Thailand's spiritual domain Photograph: Andrew Spooner

Wat Bang Phra's former abbot Luang Phor Phoem, who died a couple of years ago, was famous for creating particularly powerful sak yant (tattoos) and attracted thousands of committed devotees. The monks of the temple continue the tradition using a single thin needle about 18 inches long Photograph: Andrew Spooner

In Thai culture the sak yant is often worn as a symbol of spiritual and physical protection and they mostly display a mixture of cabalistic spells in ancient Khmer/Cambodian script or animals such as tigers and monkeys Photograph: Andrew Spooner

During the festival devotees who have been tattooed return to the temple to have their tattoos re-empowered by the monks in a large puja (festival) that attracts a couple of thousand people Photograph: Andrew Spooner

The crowds usually begin to congregate shortly after sunrise with the thick heat of the Thai summer (March and April) enveloping the gathering Photograph: Andrew Spooner

It is a deeply spiritual festival, with intoxication of any form completely forbidden and the seated monks and devotees who attend can often be glimpsed in deep meditation Photograph: Andrew Spooner

Some will sit shirtless proudly displaying large elaborate tattoos. At first, a sense of ordered calm pervades the festival. Many devotees will fall into a trance-like state Photograph: Andrew Spooner

This serenity doesn't last long. Eerie cries begin to ring out from within the crowd and a few of the devotees begin to contort their faces and bodies Photograph: Andrew Spooner

They leap to their feet, clench fists and let out long screams, clawing at the ground and air. It is a frightening and bizarre spectacle to a Westerner but many Thais will sit giggling or remain indifferent Photograph: Andrew Spooner

The devotees are in fact undergoing what they believe to be a form of possession by the animal spirits inculcated into their tattoos. Some are very clearly monkeys Photograph: Andrew Spooner

Others are tigers and buffalos. During the possession some will seemingly become enraged, attempting to charge the plinth where the senior monks are delivering the spritual prayers Photograph: Andrew Spooner

Conveniently for the leaping tigers or crouching monkeys, the crowd has already formed into neat patterns with runs cleared for possessed devotees to sprint towards the plinth Photograph: Andrew Spooner

There is an air of order amid all the wild screams and roars, with drink sellers and noodle stalls nearby should you need respite. Families with children attend - for some Thais it is an engaging day out Photograph: Andrew Spooner

To break the spell of possession the devotee must be lifted into the air and have their ears rubbed Photograph: Andrew Spooner

For this very purpose a platoon of soldiers is drafted in to protect the senior monks sitting on the plinth. Suitably calmed, the devotee immediately wanders oblivious back into the crowd Photograph: Andrew Spooner

In the past it was common for almost all Thais to be tattooed. These days many still have discreet protective sak yant placed above the hairline on the nape of the neck or use transparent sesame oil to create an invisible marking. But the tattoos from Wat Bang Phra temple are believed to have magical powers protecting against knives and guns Photograph: Andrew Spooner

Most tattoo devotees are men in 'dangerous' professions. These can include policemen and soldiers through to labourers, motorcycle taxi drivers and, of course, members of Thailand's notorious criminal underworld Photograph: Andrew Spooner

The festival ends when the monks spray holy water on to the crowd. In the minutes leading up to this, the possessions are at their most intense and can happen in large numbers. The water spraying comes as a relief in the burning heat and the crowd quickly disperses afterwards, the devotees placated for another year Photograph: Andrew Spooner

This year's festival takes place on Saturday 7 March. The date is usually the Saturday nearest the last full moon before the April Thai New Year (Songkran).

• For further reading on Thai popular culture, try Very Thai by Philip Cornwel-Smith Photograph: Andrew Spooner