Loading...
Ultras · US · TN

Viper 100

100 Miler · 100 Mile
Registration open
Registration is open.
Race dateMarch 19-20, 2027
Duration2 days
Start7:00am
Whenin 146 days

Who's going to Viper 100?

I'm running itPlan your weeks and your aid station times I'm crewingWhen to leave, where to park, at every stop I'm pacing or cheeringAsk your runner for their Out Here link

Free. You can start with nothing.

Official website Entry Aid stations Notify me if this race changes
Free, and always will be. NavRun makes money from race-day planning for runners who want it, never from this. Ultras change constantly, sometimes the morning of. Always confirm with the race director and the official website before you rely on anything here.
Distance The race
100 Mile
Climb
not checked yet
Descent
not checked yet
High point
not checked yet
Time limit The race
41:00:00
Aid stations
6
Started
not checked yet
Finished
not checked yet
Finish rate
not checked yet
The course

Where it goes multi-loop · 6 aid stations

Three 33.4-mile loops of Shelby Farms Park, starting Friday at 7:00 AM, with the park going from daylight to darkness and back again.

A runnable loop that mixes smooth paved greenways with winding dirt trails. Road shoes work well on much of the course, although trail shoes are recommended. Trekking poles are permitted but not required.

The race

What this one is

Viper is a 33.4-mile loop through Shelby Farms Park in Memphis, Tennessee, one of the largest urban parks in the country. Smooth paved greenways and winding dirt trails run past lakes, woods and open fields. Runners choose the 100 Miler, 107K, 53K or 25K, and every distance finishes at Hyde Lake.

Getting in

Getting in Entry, lottery and what the race asks of you before race day.

Lottery
not checked yet
Lottery opens
not checked yet
Lottery draw
not checked yet
Field cap
not checked yet
Registration
UltraSignup ultrasignup.com
Qualifying
not checked yet
Minimum age
not checked yet
Transfers
No ultrasignup.com
Deferrals
Yes ultrasignup.com
Crew access, pacers and drop bags

The rules that shape your day Anything marked "not checked yet" is a gap in what we hold, never a no from the race.

Crew allowed
Yes ultrasignup.com
Vehicles per runner
not checked yet
Pacers
Yes, from mile 33.40
Muling
Not allowed ultrasignup.com
Drop bags
Yes ultrasignup.com
Cupless
not checked yet
Course marking
Fully Marked ultrasignup.com
Night running
Yes mambatrailrunners.com
Dogs
not checked yet
Headphones
Allowed ultrasignup.com
Crew rules
Crew may only help at fully manned aid stations. Crew can reach the Refuge Aid Station, the Tour de Wolf Aid Station and Hyde Lake Pavilion. They cannot reach the Bridge Aid Station. No outside assistance anywhere else on the course. ultrasignup.com
Pacer rules
One pacer on the course at a time, after the runner has completed one full 33.4-mile loop. A pacer may join at any crew-accessible aid station on the second loop (Refuge, Tour de Wolf or Hyde Lake Pavilion) and may be swapped for another pacer there. Each pacer signs a waiver and wears a pacer bib. Pacers carry nothing for the runner, stay with the runner, and enter and leave aid stations with the runner. If the runner drops, the pacer leaves the course.
Drop bag rules
Drop bags are permitted at Hyde Lake Pavilion and the Tour de Wolf Aid Station. Label each bag with your name and race distance. ultrasignup.com
Cutoff philosophy
not checked yet
Aid stations

Every stop, and what you get there ● yes   ○ no   ? nobody has checked   – does not apply to this race

Mile Station Cutoff Crew access Bag Pacer Med To next
7.40 Bridge Aid Station
NoneSignal wrong?
 ? ○ ○ ? ? 3.40
10.80 Refuge Aid Station
NoneSignal wrong?
 ? ● ○ ? ? 3.60
14.40 Bridge Aid Station (second visit)
NoneSignal wrong?
 ? ○ ○ ? ? 6.40
20.80 Tour de Wolf (TDW) Aid Station
NoneSignal wrong?
 ? ● ● ? ● 6.20
27.00 Tour de Wolf (TDW) Aid Station (second visit)
NoneSignal wrong?
 ? ● ● ? ● 6.40
33.40 Hyde Lake Pavilion (Start/Finish)
NoneSignal wrong?
 ? ● ● ? ? ?
Same race, other lines

Other distances and other years

What it looks like out there

Somebody has been out there with a camera the tables say the climb is long. these say what long feels like.

Nobody has been out there with a camera or a microphone yet. A gap means nobody has found it, not that it is not out there. Seen a course preview or a film of this one? Send us the link.

Add to this page

What you know every one of these is read by a person before it changes anything

Ran this race? Tell the next runner what you know.

Nobody sees it until we have read it. No account, no sign-in.

Leave blank if it applies to the whole race.

Leave blank if it is not about one particular stop.

Optional. Something like “Cal Street, mile 62 to 78”.

Write it the way you would say it to someone at the start line.

Optional, and it decides nothing. It only tells the next runner where this is coming from.

Optional.

Optional, and never shown on the page. Only so we can ask you a question about this note.

Leave this field blank.

See something wrong or out of date? Suggest an edit.

This changes nothing on the page on its own. Somebody checks it against the race first.

Optional. Filled in for you when you start from a specific line on the page.

Copy it as it appears, so we can find it.

The corrected value.

Required. Where it came from: the race email, the runner manual, what you saw on the day.

Optional.

Optional. A screenshot or a photo of the sign works.

Optional, and it decides nothing.

Optional.

Optional, only so we can come back to you about this correction.

Leave blank if it is about the whole race.

Leave blank if it is not about one particular stop.

Leave this field blank.

Seen a course preview or a film of this one? Send it over.

Somebody watches it before it goes anywhere near this page. What we are after is footage of this course, on the ground. If it would be just as true of any other race, it is not this.

Required. A line is plenty. Where the climbs are, what the footing does, what the last twenty miles look like.

Optional, and it decides nothing.

Optional.

Optional, and never shown on the page. Only so we can ask you a question about this one.

A YouTube link, a race report, a photo gallery, whatever it is.

Optional, and we credit them on the page.

Leave this field blank.

Have the GPX? Send us the link.

We want the address of the file the race publishes, not the file. We download it from there so the page can say where the line came from.

The page or file on the race's own site.

Optional, and only so we can ask you a question about it.

Are you the race director? Get in touch and we'll make it right.

We read every one of these and we write back. Every fact here carries the source it came from, and the way a wrong one gets fixed is a person checking it against what you tell us.

Required, because this is a conversation and we write back.

Tell us what is wrong, out of date, or missing on this page. We read every one of these and we will get back to you.

Optional.

So we know who we are writing back to.

Optional. Director, assistant, comms, whoever you are.

Leave this field blank.

Where this came from. Every fact on this page records its source and when we last checked it: 81 sources for this race. Hover a source link to read the sentence it came from.
39% of what we track for a course is filled in. The rest says "not checked yet" rather than guessing.
See something wrong or out of date? Suggest an edit
Ran this race? Tell the next runner what you know
Were you out there? Say which stops a text got out from
Got footage of this course? Send us the link
Are you the race director? Get in touch and we'll make it right.
Anything else: [email protected]

Ultras change. We will tell you when this one does.

Cutoffs move, races get postponed, lotteries open and close. We read the race's own sources and record where every fact came from. Put your email in and we will send you what changed, and where we read it.

No account, and nothing to cancel.

What happens to your email. Nothing else. I do not sell it, and I will not send you anything except this race changing. One click gets you out.

I keep this catalog because the information is scattered and hard to trust. Telling you when it moves is the same job.

Ultras change. We will tell you when this one does.

Cutoffs move, races get postponed, lotteries open and close. We read the race's own sources and record where every fact came from. Put your email in and we will send you what changed, and where we read it.

No account, and nothing to cancel.

What happens to your email. Nothing else. I do not sell it, and I will not send you anything except this race changing. One click gets you out.

I keep this catalog because the information is scattered and hard to trust. Telling you when it moves is the same job.