Frosty Fat Sass

Event overview

The Frosty Fat Sass is a trail event on January 31, 2026 in West Orange, NJ at the Turtleback Rock Picnic Area in South Mountain Reservation. This is the ninth annual edition and is organized as a fundraiser for the South Mountain Conservancy. The event has raised over $20,000 for the Conservancy since 2018. Registration options include a hardship entry and multiple distance/division choices.

Distances and divisions

• 5K
• 3 hours
• 6 hours
• 3 hours - RUCKING (two weight divisions: 15 lbs lightweight and 30 lbs heavyweight; pack or ruck required, dry weight before adding water or gear; open to men, women and nonbinary athletes)

Course and logistics

The event uses a 5K loop with 289 ft of elevation gain. The route mixes wide dirt carriage roads and singletrack with rocks and roots. Details include a wide dirt first mile, a roughly 1/2-mile descent of 200+ ft at about mile one, a 100 ft climb near mile 2.5, and a rocky singletrack final mile. Course composition is about 83.87% doublewide trails and 16.13% singletrack. Portapottys are available at the start/finish area. The loop passes behind Turtleback Zoo.

Race rules and participant information

This is a self-supported fat-ass event with no aid stations, no finishers' swag, and no refunds or deferrals. For the 3- and 6-hour events, loops that are not completed before the timer ends do not count. Participants must record loops on the loop board for multi-hour events; 5K finishers write their finish time on the clipboard. Pacing is allowed for participants over age 60 and for athletes with disabilities; other pacers require prior approval. Kids under 19 are eligible for a youth discount and receive wooden star medallions when registered or spectating. Visit the organization's website for the most recent information.