Mammoth Campground (Yellowstone) is a 81-site campground in Yellowstone National Park. It accommodates car camping, camper vans, fifth wheels, and truck campers, with sites for RVs up to 99 ft. It is a no-hookup campground. Around 5 sites are shaded. Pets are welcome at some sites, most sites have a fire pit, and 6 sites are ADA-accessible. Maximum party size is 6. Like most popular Recreation.gov campgrounds, Mammoth Campground (Yellowstone) books up months ahead, but cancellations open regularly. Campsite Sniper watches the targets you choose and alerts you when one frees up. We never book, hold, or pay for reservations; you book directly on Recreation.gov.
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Tap any pin on the map to see that campsite's open dates, details, and a booking link.
Lakefront, hookups, your RV length, weekends only - set it as picky as you want.
We run paced availability checks for Mammoth Campground (Yellowstone). One watch covers every matching site.
When a match opens, you get a push with a Recreation.gov link so you can review and book it yourself.
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Mammoth Campground (Yellowstone)'s 81 sites book up months ahead on Recreation.gov; most openings come from cancellations. Pick a site on the map to see its 6-month calendar, or set a free Campsite Sniper alert to get notified when one opens. You still complete the reservation yourself on Recreation.gov.
No. Campsite Sniper sends alerts and direct Recreation.gov links. It never books, pays for, holds, hoards, or resells reservations.
In just the last 7 days, 375 cancellations opened across 62 different dates at Mammoth Campground (Yellowstone). "Sold out" rarely means sold out.