Frosty Fat Sass

Event overview

The Frosty Fat Sass is a trail running and hiking event held on January 31, 2026 in West Orange, New Jersey at the Turtleback Rock Picnic Area off Walker Road in South Mountain Reservation (374 Walker Road). It is the ninth annual running of this event and functions as a fundraiser for the South Mountain Conservancy. The event has raised over $20,000 for the Conservancy since 2018. Registration closes on January 29 at 11:59 PM ET. The organizer is Sassquad Trail Running.

Race format and course

Distances and formats:

• 5K loop
• 3-hour event
• 6-hour event

Course and rules: The 5K loop starts and finishes near the Turtleback Rock Picnic Area. The loop has 289 feet of elevation gain and combines carriage roads (dirt or gravel wide trails) and technical singletrack with rocks and roots. Specific features include a very rocky 200+ foot descent within the first half mile, a 100 foot climb near mile 2.5, and a singletrack final mile. The surface breakdown is listed as about 83.87% doublewide trails and 16.13% singletrack. Portapottys are available at the start/finish area. The event is self-supported: there are no aid stations and no finishers' swag, and participants must record loops on the loop board or write finish times on the clipboard to be included in results. The organizer will not offer refunds or deferrals. Pacers or guides are allowed for participants over 60 and for athletes with disabilities. Dogs are not permitted. A rucking division is available for the 3-hour event with 15 lb and 30 lb dry-weight pack divisions. Visit the organization's website for the most recent information.