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Rattlesnake Rally ​Gravel Grinder

May 18, 2019 @ 6:00 am - 8:00 pm PDT

|Recurring Event (See all)

An event every year that begins at 6:00 am on day third of May, repeating until May 20, 2023


In 1841 the first wagon companies were organized for Oregon and California, setting out along the North Platte River. It was this route that lead nearly 400,000 emigrants westward to follow their American dream. On a journey that would have taken these settlers days, you will complete in just hours.

2018 will mark the 6th year that bikes have been around the Rattlesnake Mountain Range! The 120 mile course starts at 7am at Poison Spider School (about 8 miles west of Casper) and travels on 10 miles of pavement before the road turns to gravel. For the next 40 miles, riders are mostly going uphill along loose gravel, dirt and hardpack gravel as you travel to the first aid station (at mile 51) and the first turn of the race. Riders loop around the western edge of the mountain range and will begin to descend Southeast towards Pathfinder reservoir. Enjoy these 25 miles on mostly dirt road with a mix of gravel and larger cobble road with a few long sections of sandy road with great views and rolling hills. It is VERY rare to see any human life this far out in the middle of nowhere. In 2013, I did not see one single vehicle in the 105 miles of gravel. In 2014, we saw 2 vehicles the entire time. Riders will find themselves at hwy 220 around mile 85 and you can enjoy 5 miles of smooth pavement on wide lanes with rumble strips. Aid station number two is at mile 90 and is our turnoff to Old Oregon Trail Road to the Northeast. The next 30 miles are glorious! You’ll point yourself northeast and go uphill slightly on good gravel road for 6 miles followed by a crazy fast 8 miles of descending along mostly dirt road. Pedal your way the final 15 miles back to Poison Spider School on mostly dirt road and BAM, you made it!!
Strava link to 120 mile course:

The 60 mile race also starts at Poison Spider School at 7am. Racers travel for 1.4 miles on pavement before turning on the Historic Old Oregon Trail Road. For 30 miles, riders will pedal pedal pedal uphill along huge fields of sagebrush, dried up creeks, jackrabbits, antelope and two historic sites. At hwy220, riders will have an aid station to grab a bite to eat before turning around and heading back to the school. It’s mostly downhill at this point and generally the wind is always at my back when I return home on this route. The road surface is primarily dirt and can be treacherous in the rain. But when it is dry, it is smoking fast. This is the same exact route that hundreds of thousands of immigrants traveled by in the mid 19th century. There are around a dozen different locations along this route where you can actually stop and see ruts made from the wagons that traveled the trail. Enjoy the history, the views and appreciate the mode of transportation you are gifted with in 2018!
Strava link to 60 mile course:

This route starts at Poison Spider School at 10am. This route is fantastic for those wanting to try out gravel grinding and those who want to dive into a little bit of history. The road is so beautiful and varies in different road surfaces. From dirt to fine gravel to ruts and rock. You’ll be feet away from the original Oregon Trail, Mormon Trail, California Trail and even the Pony Express!! Stop at the aid station at mile 8 for a drink, food and a little history if you’re interested. Continue another 10 miles past Willow Springs and up the steep 1 mile climb called Prospect Hill. At the top of the hill will be an aid station with more food and drink. Turn around there and head back where you came from. Its mostly all downhill from there!
Strive link to 37 mile course:

This route begins at 9am at Poison Spider School and heads south on Twelve Mile Road. Turn left on Iron Creek Road/308. Continue for a couple miles to the pavement and turn around in the historical site where a volunteer will be to direct you. Return to the school. At the school you will continue your journey west. Stay on Poison Spider Road West for 22 miles and turn left on Forest Oil Road. An aid station will be at this turnoff for you to refill bottles and get a bite to eat. Continue on Forest Oil Road for about 6 miles to where it ends. Turn around and return the way you came back to the school.

This route begins at 9am at Poison Spider School and goes straight west on the original Bridger Trail! This was the original gateway to the west for two years until better water sources were discovered along the Oregon Trail. You will simply stay on this road for 22 miles to the aid station. Turn around at the aid station and return to finish at the school.

FINAL day to register online.

5pm-7pm: Packet pickup

5am-5:45am: Racer check in at Poison Spider School for the 120 mile participants. NO NEW REGISTRATIONS ACCEPTED.
6am: Race begins for the 120 mile participants!
8am-8:45am: Racer check in at Poison Spider School for the 60 mile participants. NO NEW REGISTRATIONS ACCEPTED.
9am: Race begins for the 60 mile participants!
9:15am-9:45am: Racer check in at Poison Spider School for the 40 mile participants.
10am: Race begins for the 40 mile participants!

6:00pm-10pm: Afterparty begins at the TBD! We will be rocking out to some excellent live music that will have you dancing all night! This venue has great bathrooms. Awards will start at 7:00pm.


May 18, 2019
6:00 am - 8:00 pm
Event Category:


Poison Spider School
9664 Oregon Trail Rd
Casper, WY 82604 United States
+ Google Map

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Event details subject to change; check event websites for details.