[slideshow: adult-soap-box-derby,left,5032a96c1a5a49000500000a]

For one Saturday morning in August, the PDX Adult Soapbox Derby takes over an otherwise peaceful Mount Tabor Park. From the finish line twisting all the way to the top of the extinct volcano, crowds of onlookers drink, cheer and snap photos of the stunning cars and racers as they fly by.

In its 16th year, the Adult Soapbox Derby has come a long way from its humble Portland beginnings. The official site conjures the image of six men drinking beer and racing down Mount Tabor in handmade soapbox derby cars. But don’t mistake this for some Portlandia glorification of a childhood pastime. The PDX Adult Soapbox Derby is truly special.

This year’s event featured 42 cars, ranging from lightning quick science cars to the inspiring and hilarious art cars. A giant bathtub disqualified for spilling too many bubbles on the course, Hunter S. Thompson swatting at swarms of invisible bats, a giant bottom feeder with a motorized tail, The Red Baron, a casket and a beauty salon all zoomed down the hill.

The logistics of the actual event are equally amazing. After 16 years, the Derby is still grass roots and volunteer driven, and free of commercial vendors. Even with crowds that reach upwards of thousands, and a lot of day-drinking (beer is allowed in the park), the event seemed fun, light and under control. And by 4 pm, when the late spectators started packing the course, another adult soapbox derby successfully came to an end.

If you were one of the unlucky ones to arrive too late or miss it completely, check out our slideshow. And thankfully, there’s always next year.

Interested in racing next year? There’s some information here. But be forewarned — word around the race is that lines for sign-up start at 4 am the night before. And by 5 am, all 42 spots are gone!

This story originally appeared on Oregon Public Broadcasting.