Seth’s Fat Ass 50K

Overview

When: Saturday December 12, 2026

Where: Forest Park – Springfield, MA

Cost: The race entry fee are as follows

50K Individual: $45 / $50 (late registration) plus Ultrasignup fees.

50K Relay: $90 / $100 (late registration) plus Ultra signup fees.

Online Registration:

https://ultrasignup.com/register.aspx?eid=8220https://ultrasignup.com/register.aspx?eid=8220

New option this year….two person relay. You can split the laps however you and your teammate want.

Race Day Registration: Is available, cost is $50 by cash or card

Paper Registration Form (for Race Day only)

Race Details

Race Details 2026: Saturday 12/12 starting at 8:30am.

Check-in begins at 7:45am

You’ll have 7 hours to complete one, two, three or all ten 5K loops. Remember, you can stop after any loop, do one OR do them all.

The course is most of ‘Bright Nights’ route, so road should be clean, the course is NOT closed to traffic but traffic should be limited on this course.

Start Area

In the lot near the baseball fields, same as the last 6+ years.

Parking

Bullet items 1 & 2 below are most accessible from the main entrance to Forest Park on Sumner Avenue.

Plenty of parking is available in the lot near the baseball fields (https://goo.gl/maps/ZcrUvcpVn8a7CZca6)
There is plenty of parking also located on North Greeting Road
245 Park Drive Longmeadow, MA. Note this parking is NOT located within Forest Park & it is a 1/2+ mile walk to start. Locals typically like this entrance as they can run to the start for some extra miles before the race.

Please note parking within Forest Park requires you to pay a small parking fee, that is NOT included in registration. There may be a parking attendant at the main entrance on Sumner Avenue.