Mammoth Campground

Dates: April 24 - 30. Yellowstone is just awesome. If you know what you are getting into there won't be much negative to say. There was wildlife that would stroll through the campground at will which can be a bit scary and dangerous but if you aren't an idiot then it is very, very cool! There weren't any hookups but we knew that going into it and there was a water fill spot which was nice. They did have bathrooms for everyone that didn't have onboard bathrooms. Site was actually quite level which was a surprise. Verizon signal was also fairly decent (it is non existent once you travel into the park proper). Generator use was allowed from 8am to 10pm.

We stayed here for 3 nights using the first come for cancellations method, each morning. We would be in line by at least 7 and we're able to get a cancelled site each day. Not too bad for not having reservations going to Yellowstone. The sites are open and sunny in the sagebrush. A bit noisy, though, as it is on the S curve of the main entrance to Yellowstone. It is also quite a ways to the Southern activities in the park. Makes for some longer days home. It is very close to Gardiner, so gas and food is cheaper. Overall, a great spot for the northern half of the park.

Pros: Clean bathrooms, easy to access dumpsters, big bear boxes, easy pull-through, accessible to seeing the park, friendly hosts, some shade, some sun which helped with the solar panels
Cons: Terraced so that there isn't a lot of privacy from those below you and around you.

The site we were in was nice and we were lucky to have a fresh water pump right next to our camp site. We really liked how well maintained everything was and it was very easy to pull through our site. The gravel wasn't that level, but that's what leveling blocks are for. Right?

Bonus: Elk walked right through the campground and lingered in sites 62 and 63...so right next to us.

We stayed here in mid-May from the 16th-20th. We had a tough time finding a spot to camp at in Yellowstone initially as the first campground we booked through Xanterra for our first planned dates were cancelled by the agency for reasons unknown. We then found out, after some online searching and a forum through TripAdvisor, that Recreation.gov and Yellowstone began a new partnership that would allow campers to choose their campsite online instead of betting on the first-come first-served system. This was really helpful for us, as we were traveling from miles away and had no idea when we would be able to make it to the campsite.

Our site was clean and level. It is a pull through site, but it doesn’t join another campsite’s area like a lot of the other ones did. It was fairly shaded, but nice for the time we were there. The sun was out a lot so that helped our solar panel with charging our batteries to keep our fridge running as this whole campsite does not have electricity or showers. The nighttime was especially nice because of the non-electric atmosphere, making it hard for many people to play their music and have a whole lot of lights out on their campers. Cooking wasn’t hard either, and the camp and park rangers request that all of your food you make is eaten immediately and not left out. All trash is to be disposed of in your camper or the special trash bins they have throughout the park. The firewood you can buy at the campsite was good for s’mores as long as you don’t make too much of a mess in order to not attract bears and other animals into the area. We did feel safe with the camp hosts patrolling the area often and making sure everything was in order. The camp rules say that you can only run your generator from 8am-8pm, but that gets hard sometimes when you get back late. We didn’t have anyone tell us that we needed to turn it off, and our generator was pretty quiet, so the trucks driving by were louder than our generator.

We didn’t see any bears or bison in our campsite, though there was evidence of bison right by our campsite. We did, however, see a group of elk in the area by our campsite and a very pretty magpie that flew around the entrance, as well as several prairie dogs. The accessibility to the Lamar Valley area and Mammoth Hotsprings and Gardiner was nice as well. If you stay here, be prepared for amazing views and lots of memories!

We were there mid to late October. While there are no hookups, we did like the heated rest rooms with flush toilets, hot running water, and electric plugs (we used our inverter but saw several times that folks were charging their phones in the restrooms). We were arriving on a Saturday, so we got in line at the entrance at 5:55. There were 3 rigs ahead of us and many came after. The rangers started processing site assignments at 7am. We were assigned a site a little before 8am. The pull-thru site made setting up quick, which was nice since it was 26 degrees outside.
We liked the proximity to Lamar Valley, and drove it many times. Saw bear, bison, pronghorn, an eagle, coyotes and wolves. Even saw coyotes with a bison kill. On one of the days that had snow, we enjoyed a drive through Lamar Valley to Cooke City. Great burgers at the Bistro Cafe. The scenery heading out of the park and on the way to Cooke City is spectacular and worth the drive.
We also drove to the Grand Canyon, Old Faithful and Midway Geyser basin from Mammoth, although they are easier reached from other campgrounds in the park (but they were all closed for the winter).
There was no cell coverage in the campground, but a short drive toward Gardner brought us in range, at a large pullout before the entrance gate. Added benefit, we saw bighorn sheep along the way! The campground is near the main highway, but I was surprised that the road noise was no bother. Of course, with the winter temperatures and being on the go most of the time, we didn’t sit outside. We did go through propane, and refilled our tanks at the Sinclair station just outside the northern edge of Gardner. All the dump stations in the park were closed for the winter—before arriving we used the dump station at Grizzly RV Park in West Yellowstone. We had hoped to use them again when we left Mammoth, but they were closed. We were driving south into Idaho so we used the dump station 95 miles south in Rigsby at Bob’s Kwik Service.
The elk herd that stays around Mammoth headquarters/store did come down to the campground one day, fun to see (keeping a distance). Another day a large bull elk with 2 females across the road did an impressive display of bugling, countered by another bull up behind us.
Many of the days we were at Mammoth were snow days, and park staff worked quickly to clear the roads. Finally the weather predictions were for -10 degrees in a couple days, and it was time to head south! By the time we left, the campground had only about four occupants.

When we arrived at 9 am on a Wednesday in mid-September, we were 3rd in line for an RV campsite, 6th overall. The campground filled by 11 am. Since it is a walk-in campground, you do need to arrive early, as the rangers keep track of your spot in line and campsites are assigned in order of arrival as the sites are vacated.

The campground is close to Mammoth Hot Springs and the Albright Visitors Center where there is free WiFi available (tip: for best WiFi speed, sit on the front porch of the Visitors Center after closing time). There are plenty of threaded water spigots around the campground (but no dump station — we dumped at Yellowstone RV Park in Gardiner, MT). Cell service was 3 bars Union - US Telephone 3G, but we didn’t get to use it much because of the roaming limit we have on our cell plan.

We were assigned a pull-through site, #12 (I think all sites are pull-throughs) right next to the highway. Other than the road noise, it was a pretty nice site with lots of sun for the solar panel. There was a lot of low brush between campsites, which was nice for a bit of privacy, and we were right next to a threaded potable water spigot. The sites are fairly level and it is pretty easy to get in and out of the campground.

We really liked our time here. All the campsites are pull through with great views of Lava valley. We had elk in the campground daily. All the bathrooms were very clean and whole campground is well maintained. It did fill up daily. Every morning at about 8 a line starts to form which doesn’t make sense because check out isn’t until 10. If you have to be in this place then get here around 10. Otherwise you could probably push it to noon or so but then it is probably going to be close.

The Mammoth Springs Lodge has excellent showers you can use that cost $5. Campground is a short steep hike to Visitor Center and Mammoth Springs.

Cell phone is pretty reliable on Verizon but does tend to drop unexpectedly. ATT doesn’t exist.

Mammoth is the best (and only) option for year-round camping in the park. For this reason, it is my go-to for camping on opening weekend and closing weekend each year. Camp can fill up quickly once the park roads open in spring and close in the fall so arrive early to secure a site. During the off season its not unusual for only one bathroom to be open. Almost all of the sites are level and are pull through, large enough for most RVs. Fire rings, tent pads and tables at each site. Flush toilets and water taps throughout camp. Firewood vending machine is available if needed. If the camp host is on duty to check you in you can ask to drive around and preview the sites before they assign one to you. While your fellow campers are generally quiet and respectful the location of the camp tends to be pretty noisy since the park road is routed around the camp. Be prepared to listen to park employees starting out their day driving by at 5am - snow plows, garbage trucks, etc. Lots of traffic noise all night.
And, if you're here in the fall, you'll get to listen to the bull elk bugling all night long. I'd rather listen to them than trucks any day!

This place fills up fast even in October we stayed here 10-2-18 we want to soak in the boiling river, we did all day long it was great ! the best spots are on the outer rim try for 42 through 49. No showers but they have flush toilets, portable water and trash. Gardiner is close by they have a good pizza place Yellowstone pizza company we eat there twice and if you are looking for free WiFi go to the library in Gardiner and park at the park its right across the street you don't even have to get out of your car.