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Get Tough. Get Muddy. Get it Done.

2026 Registration Now Open

Sign up before someone tougher does.

Register Now, Regret Nothing
Think you're tough? Prove it.

No training plan. No mercy. All fun.

A guy crawling through the mud at Sunday River's Tough Mountain Challenge.

TOUGH MOUNTAIN CHALLENGE

You’re not here to win. You’re here to survive 5K of mud, water, walls, woods, and whatever else we feel like throwing at you.

Sign up now for the lowest price and score early lodging deals—because pain is temporary, but overpaying is forever.

Race day is Saturday, July 25, 2026.

Participants at the Tough Mountain Challenge at Sunday River Resort, in Newry, Maine, climb up the side of a trail covered with water, tires, and rope during the obstacle course.

2026 Lodging Deal

Early registrants get exclusive access to Tough Mountain lodging deals. Why? Because you didn’t wait around like a maybe. You committed. You’re in. Now enjoy the perks.

Save up to 20% on resort lodging on Tough Mountain Challenge weekend using promo code TMC.

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TMC? MMC? WTF?

Learn More. Then Sign Up Anyway.

  • An athlete with goggled climbing up the hill at the Tough Mountain Challenge at Sunday River.
    Walls, Hills, Hurt

    Tough Mountain Challenge

    Want a prime heat? Better move—early spots go faster than your grip on a muddy wall.

    Register NowNeed More Info?
  • A young child competing in the Mini Mountain Challenge
    Let the kids loose

    Mini Mountain Challenge

    Registration for 2026 opening in the fall!

    Mini Mountain
  • A group of athletes finishing the line of the Tough Mountain Challenge
    All the Dirty Details

    About The Race

    Need more convincing? Okay, here are some more details.

    Don't Chicken Out
It's not pretty, that's the point

Pain Looks Good on You

A man with his tongue out crawling through mud at the Tough Mountain Challenge.A man going through a muddle obstacle at Sunday River's Tough Mountain Challenge.Athletes jumping through muddy pits at Sunday River's Tough Mountain Challenge.Athletes climbing up a super tall hill at Sunday River's Tough Mountain Challenge.A woman smiling in a mud pit at Sunday River's Tough Mountain Challenge.A man and a woman going down a slide, with their hands in the air, at Sunday River's Tough Mountain Challenge.A man receiving his medal after finishing the Tough Mountain Challenge.
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