Route Options

Filthy 50

Start Time

10:00 AM

Starting @


$5 January 17

$5 February 21

$5 March 20

$10 April 12

Filthy 50


The Filthy 50 was added in 2019 and it is becoming quite the popular course due to it's remoteness and grittyness. When we first explored the 20 mile branch, dogs weren't sure how to react to cyclists (some still don't react). The smell of manure really, really close brought back memories of my time in the Alps. The course will also take you through a tunnel underneath Interstate 96. There are some very talented artists that decorated the tunnel, so be sure to check this bonus feature out! So in short, this course will probably take you to places your GPS won't go to voluntarily. It's worth every minute of it though! After you hop back onto the 30 mile route, Ivan the Terrible will be waiting to see what you are made of!

The Filthy 50 is part of the Michigan Gravel Race Series (MGRS) and designated as the Long Course.

Register Now

Included with registration:

  • Customized plate with chip timing by Epic Timing
  • Swag bag
  • Well marked course with volunteers and police at pre-determined intersections
  • 3 aid stations


  • Top 10 overall will be recognized and get very nice medals and prizes


  • 17 and under
  • 18-29
  • 30-39
  • 40-49
  • 50-59
  • 60-69
  • 70+
  • Mountain Bike
  • Fat Bike
  • Single Speed
  • Athena
  • Clydesdale
  • Tandem
  • Unicycle

Team Competition

Minimum of 4 registrants. Top 4 times to be totaled. The lowest total team time wins the Team Competition. Everyone on the team gets a custom Dirty 30 Cup (not just the top 4).


the Terrible
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