MAY 4, 2024
Rising from its own ashes…
Get ready to once again meet the GRIM REAPER at Onyx Summit!

General Information and Ride Rules – Please Read!

Click here for Breathless Agony 1997-2016 historical data maintained by Chuck Bramwell.

2024 Entry Fees *:
Until April 27th: $  TBD. Late entry: $ TBD cash with online reservation.

Entry includes a date with the Grim Reaper; automatic participation in King of the Mountains Century Challenge (if you also completed Mulholland Challenge); route sheet and downloadable GPS files; chip timing with overall and age category results posted online; fully stocked checkpoints along the route with a large selection of snacks and drinks; roving SAG support; refreshments at Onyx Summit.

Please read our registration and cancellation policies.

If you’re able to recruit an event volunteer, please email us before signing up and we’ll give you a coupon code to use during registration for an instant 50% off.

Sign Up

Please read
the rules and our cancellation policy before registering.

Use the SignUp bottom to register online and pay by credit card (which includes a small service fee). 

Start / Finish Location:



Check In:  
Friday night from 7pm to 8:30pm at LOCATION TBD. Saturday morning from 6am to 7:45am.


If you’re a super fast rider and leave before your suggested starting time, you may reach a checkpoint before it opens – and you’ll have to wait, or ride self-supported.

Time Limit:
9 hours – based on the earliest start at 7am. All riders must reach the summit by 4pm.

Ride Description:
Though not anticipated, last-minute routing changes may be required. Links to the maps and download files are below; but are subject to change.

This event is for the cyclist who loves to climb. Bring gears! Some of the roads have steep sustained climbs of 9-10%.

Route Sheets and GPS Files:
Please note that advance route sheets and gps files are provided as a courtesy and you use them at your own risk. Planet Ultra doesn’t guarantee accuracy. Please further note the following very important caveats:

  1. A few days before the event, Planet Ultra will email an invitation to the RWGPS “event” with all routes. The links in the invitation allow you to use subscription-based functions even if you only have a free account.
  2. Never depend solely on a bike mounted GPS. Bring your route sheet, and know how to follow it. Use the RWGPS app on your smart phone as backup.
  3. GPS batteries on many “bicycle” GPS units may not last for a century. Make sure you’ve arranged for additional power.

Routing and Navigation:
Planet Ultra route sheets include lots of information to help riders navigate the course: Stop sign (SS), traffic light (TL) or T-intersection (T-int). We know riders prefer course markings; however, many of the towns/cities/counties specifically forbid it and in some areas traffic makes it unsafe.
For these reasons we no longer mark courses at our events. 
We trust that as a seasoned endurance rider, ready and willing to ride 100+, you’re proficient at reading a route sheet and/or you’ve invested in a GPS based cycling computer into which you can upload the route (and we strongly advise that you use one). Your entry fee includes access to RideWithGPS downloads for your Garmin (or other GPS devise) or your smart phone.

Personal SAG Vehicles:
Not allowed between start and Onyx Summit! If you bring one, you’ll be DQ from the event without warning. Personal SAG is any vehicle (motor or otherwise), anywhere on the route, operated by someone other than Planet Ultra staff, that is providing any type of aid, assistance, or motivation, or taking photographs, or simply out cheering. Our permits don’t allow dozens of extra vehicles on the roads or at the checkpoint locations. Imagine the traffic! If you’re bringing someone who wants to be out on the course, please have them contact us and join our volunteer staff.

We always need volunteers! Click here for info about available positions.