Frosty Fat Sass

West Orange, United States • 31 Jan 2026

Event details

The Frosty Fat Sass is a trail running and hiking event in West Orange, NJ at the Turtleback Rock Picnic Area in South Mountain Reservation on January 31, 2026. The organizer is Sassquad Trail Running and the event is a fundraiser for the South Mountain Conservancy; funds raised are donated to that nonprofit. Registration closes Friday, Jan 30 at 11:59 PM ET. Event options include:

  • 5K
  • 3 hours
  • 6 hours
  • 3 hours - Rucking division (see below)

This is a self-supported "fat-ass" format: there are no aid stations, no finishers' swag, and participants must record their loops on the loop board or write finish times for the 5K to be included in final results. Dogs are not allowed. Discounts and youth and senior accommodations are offered by the organizer.

Course and special rules

The event uses a 5K loop with 289 ft of elevation gain. The course combines wide carriage roads and technical singletrack with rocks and roots. Specific features noted by the organizer: a very rocky half-mile descent of 200+ ft near mile one, a 100 ft climb near mile 2.5, and a singletrack final mile. Portapottys are available at the start/finish parking area. For the 3- and 6-hour events, loops not completed before the timer ends do not count. The organizer recommends grippy shoes and may provide trail condition and winter traction recommendations before the event.

Rucking division: added for the 3-hour event with two dry-weight pack divisions, 15 lbs and 30 lbs, to be carried in a pack or ruck (weight vests not permitted); competitors choose division at check-in. Visit the organization's website for the most recent information.

Race information

6 km
6 Hour
3 km
3 Hour
5 km
289 m+
Visit the organization's website for the most recent information.
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