SHIMOSUWA, Japan -- Straddling a giant log, six men peer over the edge of a steep slope. There they teeter as buglers and bards, dressed in bright robes and knickers, whip up the crowd.

Suddenly, a green flag goes up and the log hurtles down the 100-yard incline, twisting and bucking and throwing most of its riders along the way.

"Someone always gets hurt. I fell off and broke a rib on my first time down," said Kazuaki Miyasaka, a spry 60-year-old former sushi chef who said Friday's ride was his fourth -- and final.

It's an unusually cavalier stunt in a country where decorum is cherished. But when it comes to Japanese festivals, the usual rules of conduct don't apply.

Every year, the Japanese stage thousands of festivals, big and small, celebrating traditions dating back centuries. Some stem from the country's indigenous Shinto religion while others have ties to Buddhism or play on superstitions about the need to ward off evil spirits.

Mostly, though, they offer people a rare chance to let loose, and many take advantage of that by being outlandish or getting raucously drunk.

For sheer over-the-top zeal, nothing beats the "Onbashira" or Sacred Pillar festival, a Shinto tradition dating back more than 1,200 years.

Held once every six years in the central Japanese towns along Suwa Lake, the festival combines nature worship with a dash of bravado and derring-do.

It involves people going out into nearby mountains and cutting ancient trees, then hauling them into their town -- a feat accompanied by much fanfare. -- to stand at the corners of local shrines.

According to Shinto tradition, deities dwell in the trees and the posts are supposed to bring spiritual renewal to the shrines, which represent the gods of hunting, farming, wind and water.

The Onbashira is one of Japan's biggest festivals, attracting some 2 million spectators. Thousands of townspeople take part.

On Friday, dozens of men and a few women in aprons or waist-length robes, knickers and split-toed, knee-high shoes gathered near eight logs cut earlier this year from fir trees hundreds of years old. The biggest measured more than three feet across and 50 feet long and weighed over 13 tons.

After a Shinto priest performed a purification ceremony with chants and a sprinkling of salt, everyone took sides along two massive straw ropes and began hauling three of them, leaving the others to be moved in the days ahead.

It was slow going: Nearly eight hours after the groups begin steering the monstrous trunks along the narrow mountain path, they arrived at the ledge for the "kiotoshi," the log ride that is by far the biggest tourist draw.

And it doesn't disappoint. Think of it as a mix of religion, show and extreme sport.

One minute, the riders are atop the log as fireworks explode, bards sing folk songs and buglers belt out a cavalry charge tune. Then the log's last support is chopped away and they're off -- barreling down the hill, trying without much success to stay on.

Almost every year, a few riders -- or onlookers -- die and dozens more are hurt. That's why festival officials now choose riders beforehand based on fitness and experience. And former riders like six-time downhiller, Hajime Okubo, coach neophytes on the fine points of leaning and holding on.

But danger is part of the thrill, says Kunitake Fujimori, the 39-year-old owner of a construction firm who rode at the coveted head of the biggest of the day's logs. If it weren't for the risks, the festivities might lose their excitement.

"It gets the blood pumping," Fujimori said.

Miyasaka, the 60-year-old veteran, puts it differently: "Without the ride, it just wouldn't be a festival."