100k Information

100k Race Details

The Worlds End 100k is a 63.8 mile single loop trail ultramarathon on 95% single-track/double-track. The course has an elevation gain of 12,395 ft with a net elevation change of 24,790 ft. We support you with 12 aid stations and challenge you with a strict 19 hour cutoff. We have a reputation as one of the toughest, most scenic trail 100k’s in the country.

Western States Qualifier
Honored to be a qualifying race for the Western States 100.

Worlds End 100k Details:
Event date: Saturday June 1, 2024
Start time: 5:00AM
Cutoff time: 12 Midnight (19 hours)
Start/Finish: Cliff Pavilion at Worlds End State Park
     *Bib Pick Up: Friday 5:30PM to 7:45PM (Mandatory for all runners)
     *Pre-Race Meeting: Friday 7:15PM (Highly Recommended)
     *Race Check-in: Saturday 4:00AM to 5:00AM (Mandatory check-in)

Registration is first come, first served and there is a qualifying standard for the 100k race.
2024 Registration Date: December 2, 2023 (6PM).
Capacity: 175 runners
Cost: $195

100k Registration

Qualification Standard:
The difficulty of the terrain means this is NOT an entry-level race. Each potential participant will be reviewed by the race directors after we receive the completed registration. At a minimum, all participants must have completed at least one 50k trail race within the advertised cut-off time before signing up. This must be within 2 years of the registration date. If you have a race that is not a 50k but has a high degree of difficulty, it may be an exception to the above standard, just email us to find out if the race may qualify you. Be sure that your race is an official race with results published on a publicly available website. Timed races can not be used as a qualifying race. You must have completed a qualifying race before registering.

Refunds: We will refund 50% of your entry fee minus any processing fees until April 6. Between April 7 and May 11, we will refund 25% of your entry fee minus any processing fees. No refunds after May 24, 2024. Race registrations are not transferable to other participants or future races, and transferring between distances (up or down) is not allowed. Please consider these factors very carefully before registering. Please use your registration profile to request a refund. Due to maintaining a waiting list, we do not do deferrals, bib transfers, or race distance switches.

Request a Refund

Driving Directions:
Button below will open Google Maps and allows you to put your home address in to get instant directions to the race!

Driving Directions to Race Parking

Participant Guide:
You will receive a hard copy of this guide book at bib pick up.

2022 Participant Guide (2024 will be ready registration day)

100k Course Information

Below you will find the official elevation profile, course map, and aid station planner. You can download them to your computer and print them. If you would like to see a more interactive map of the course with an elevation profile, see our hellodrifter.com map.

Course Record Holders


Nicole Yokum

Women's 100k Course Record
13:23:05 ('21)


Wesley Atkinson

Men's 100k Course Record
10:50:38 ('19)

Aid Station Information

In an effort to be more sustainable and friendly towards the environment, the Worlds End Ultramarathon is a cupless races. All runners will need to carry their own reusable cup throughout the race to use at aid stations.

The use of Ibuprofen or Naprosyn can lead to kidney problems when used in abundance and/or under stressful conditions. Aid stations will not provide these medications to any runner. If you feel the need to bring and use your own pain medications or anti-inflammatories, then you are willing to assume the responsibility for their use.

The aid stations are well stocked with fluids and a variety of foods. The fluids that are generally available are: water, hydration/energy drink, ginger ale and cola. The late stage aid stations will also generally have soup and hot coffee. The foods that are generally available are: salt replacement foods such as saltines, pretzels, chips; fruits such as oranges, bananas, and melons; potatoes, cookies, candies, sandwiches, etc. Aid stations also try to have their own unique foods available throughout the course. Generally vegetarian options are available but we cannot guarantee the ability to accommodate all dietary choices and restrictions.

Particpant & Wait List

We maintain a wait list through RunSignUp. As runners withdraw from the race, people on the wait list will be given an opportunity to register for the race based on the order they registered. Selected participants will be notified via email once selected and have one week to register once the email is sent. The odds of getting into the race depend primarily on the amount of turnover from the registered runners list. Since we don’t have any control over this, your guess is as good as ours. When registering on the wait list, you will be charged only if you are selected from the wait list and you accept the invitation to become a registered runner.

*** To see what position you are on the wait list, sign into RunSignUp and click on your profile, then "My Waiting Lists/Lotteries" from the left hand column. Once on that page, click "See More Details". You won't be able to see names, just how many people are ahead of you on the list.

Once you register, your credit card will be processed immediately. We will refund 50% or 25% of your entry fee minus any processing fees until the time stated in our refund policy. Race registrations are not transferable to other participants or future races, and transferring between distances (up or down) is not allowed. If you would like to move to another distance, you will need to accept a refund and register on the wait list for the distance you would like to run.

Participant List

Race Rules

As it is in many ultramarathons, the Worlds End Ultramarathon has its own rules and practices. Please carefully read the race rules before the competition. It is the responsibility of each runner and their crew to read the rules and adhere to them on race day.

Runner Rules - Runners in this event must abide by the following rules. Violation of any rule or communication by race officials may result in disqualification, fines, and being barred from future races.

  1. No unofficial or unregistered runners are permitted.
  2. Every runner's bib must be clearly visible on the front of the body at all times.
  3. Runners must follow the marked course at all times. It will be clearly marked with orange survey ribbon and reflective tape when appropriate. Directional arrows may be used where needed. Any runner that departs the marked course must return to the point of departure before continuing. Cutting the switchbacks is considered cheating.
  4. A headlamp or similar lighting is mandatory if you are running in the dark. Runners may not proceed out of an aid station in the dark without some type of lighting device.
  5. Hiking poles, headphones, GPS devices, heart rate monitors, and similar devices are allowed but only if used safely and responsibly.
  6. Crew access and drop bags are only allowed at designated aid stations. No one is allowed to drop or store supplies along the race route and runners are not allowed outside aid between checkpoints unless it is an emergency.
  7. No pets on the course. Pets are welcome at the start/finish area and with crews but they must be under control and leashed within the state park.
  8. Littering of any kind is strictly prohibited. We are operating under permits from the Department of Conservation and Natural Resources and litter could threaten future permits. Anyone caught intentionally littering along the course will be disqualified.
  9. Race staff will be tracking runner's progress around the course and it’s the responsibility of the runner to make sure the race bib is visible to communication teams and to check IN and OUT of each aid station, even if you are just passing through without stopping. The communications team at the aid station will record your arrival and relay your progress to race headquarters.
  10. Aid station captains will strictly enforce the cut-off times that are posted for designated aid stations. Runners must check OUT of the aid station before the cut-off time. Runners who return to an aid station after the cut-off time will be pulled from the race.
  11. Aid station captains have the authority to pull runners from the course if it is clear that you are physically unable to continue in a safe manner.
  12. If any runner can’t complete the race, they must notify an aid station captain and surrender their race bib, which will officially withdraw them from the race. If a runner leaves the race and doesn’t show up at the next aid station within a reasonable time, we’ll assume they’re lost and will notify authorities. This could threaten the race’s future permits. Leaving a race without informing an aid station captain may mean disqualification and restriction from entry in future races.
  13. When you sign up for the race, you are signing up to run/race at the event. We have an obligation to our participants who actually show up to the race, and we guarantee to provide a race bib, event timing, start line, a marked course with aid along the way, finish line, and results posted online through our timing company. Anything not listed above is a bonus provided by the race and is not included in your registration fee.
  14. The race will do everything they can to provide an adequately marked trail, but it is necessary for runners to continually remain alert as they run the course. On occasion, weather, animals, and persons not associated with the event can alter or remove course markings. A working knowledge of the course is highly encouraged. You are ultimately responsible to follow the correct course. You can also carry the course using your phone’s built-in GPS to see your location on the course at all times even while in airplane mode or without cell coverage. Cell coverage is poor or nonexistent in portions throughout the course.
  15. All runners and their crews are responsible to know the rules prior to participating on race day.
  16. Any runner who crosses the finish line after the 19 hour limit will not be an official finisher.

Crew/Pacer Information

Welcome spectators, family members, crews and pacers to the Worlds End Ultramarathon! Please take some time to review this section as it contains some important logistic and safety information just for you.

Pacer Rules - 100k runners may use pacers, according to the following rules.

  1. Pacers must complete an emergency contact form and a waiver at the aid station they plan to start running from. The pacer bib must be worn while on the course with the runner.
  2. Pacers may enter the course only at AS7-High Knob, AS8-Dry Run, and AS10-Brunnerdale.
  3. Only one pacer per runner at a time. Runners may use multiple pacers but only in series.
  4. Pacers are for safety and moral encouragement. Pacers can help runners at aid stations just as a crew would, but they aren’t allowed to carry water, food, or other supplies for the runner or physically assist the runner in any way out on the trail. They may run beside you or behind you, but not in front of you – this is your race, not theirs.
  5. Pacers are free to use the aid stations they visit with their runner.
  6. All pacers are responsible to know the rules prior to participating on race day.

Crew Rules - A crew can be an important part of your race effort, and they are welcome for both 50k and 100k runners, according to the following rules.

  1. Crew can help a runner in pretty much any way but ONLY while you are checked in at the aid station – nowhere else along the race route. Crews are NOT PERMITTED at AS1-High Rock, AS3-Devil's Garden, AS6-Coal Mine, AS9-McCarty, or AS11-The Gate.
  2. Parking is limited at many of the remote aid stations and some of the access roads are narrow and dusty. Crews should limit themselves to one vehicle to reduce congestion and provide a safer course environment.
  3. Aid stations can be busy places and it’s important that runners have a clear route in and out, with easy and quick access to the station. Please find an out-of-the-way place (but within 50 yards of the station) for crew activities and obey the instructions of the Aid Station captain as the aid station is their space and their responsibility.
  4. We’re really one big trail family when it comes down to it… crews are free to help other runners if they want to, or to help out the aid station crew (if its alright with the aid station captain).

Failure of crew members to obey race rules:
Crews that fail to follow the above race rules will result in their runners being disqualified from the race. Cell coverage and internet access is extremely limited at Worlds End and the surrounding area. Because of this, we provide hard copies of the participant guide at the race that include race rules, maps, directions and information to help navigate your way through the race. Even so, we still advise you to read through this information before race day so you are at least acquainted with the information. Crews and pacers must adhere to the information published and ultimately, the runner is responsible for all his or her crew and pacers actions on race day.

Aid Station Access:
Crews may only visit the aid stations that are crew accessible per the aid station planner. Please don't try to visit the other aid stations because they either have difficult access or extremely limited parking that needs to be utilized by aid station staff.

Parking and Unloading:
Crew members should exercise extreme caution when driving between aid stations keeping in mind that many of the roads that you will be traveling on are narrow, remote, gravel roads – so please keep speed at or well below the posted speed limits and exercise extreme caution when approaching aid stations as these areas are where runners follow or cross the road.

Crews should park in designated areas only and at the aid stations where there is no parking lot, PARK ON ONE SIDE OF THE ROAD ONLY. Never stop or unload in front of an aid station. RVs and motor-homes are not allowed at any of the aid stations due to the gravel roads leading to aid stations where cars will also be parked on one side of the road.

Post Race:
Please park in the main parking lots at Worlds End State Park. Finish line food and refreshments are for registered runners only (and a pacer if you finish with one.) Crews and pacers are more than welcome to participate in the finish line celebration but please come prepared and bring your own food to the party.

Results for both races will be posted by Falcon Timing when they have internet service. Runners will be tracked in and out of aid stations but there can be gaps, delays or omissions in this information – we consider this information as being there for “entertainment purposes only” and not considered official. Unless there is a legitimate fear that there is an emergency we will not query the specific location of your runner at the finish line on Saturday as we need to keep our communication channels open for emergency communications.