Campsite #20 Features: Drive-In access, Pull-through parking, 50ft driveway, Fire ring w/ Grill, Food Storage Locker, Picnic Table, Pets Allowed
Campsite Reviews (3)
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@BellaC4711796· Camped on Jun 8, 2022 at Campsite #20
I love the level site for my 8x8 tent.
It would be great to have some facilities for dish washing as other campgrounds in the Yellowstone National Park. Given the likelihood to attract bears, we cannot wash/pour used water outside, yet we need to cook.
@PamelaN458· Camped on Sep 1, 2021 at Campsite #20
We were in site 20A in Mammoth campground, which is very close to the main road. The traffic noise was terrible. Huge noisy asphalt trucks we’re going up and down the road all day starting about 5:30 in the morning and continuing until late afternoon and sometimes into the evening for road construction. These sites which are so close to the road should be closed. Don’t reserve any sites below number 35 A. This was a very unpleasant experience compared to our prior stays at this campground.
@DennisD885· Camped on May 1, 2021 at Campsite #20
We have visited Mammoth Campground for many decades. In May it is the choice for the northern tier of YNP which is our area of primary interest since wildlife watching is what we are there for at that time of year. Lamar valley is where we spend most of our waking hours looking for all sorts of wildlife but especially wolves and grizzly bears. However, we love watching everything in the air and on the ground. When the road opens to Hayden valley we head that direction to watch whatever is available to see there. In our opinion everything in YNP is a must see destination and totally based on available time. Mammoth CG is good for us since we travel with a 5th wheel and many sites will work for us. CG hosts are always friendly and courteous. This and every year we only have one and its always the same complaint. Visitors seem to think that sagebrush is a perfect source for firewood. Many visitors would not know the difference between a dead branch vs. a live branch. This trip we continued to observe many people at different sites destroy them with axes, hatchets, or by hand just twisting them out of the ground. Most often its early in the morning or late evening. We think that the best solution to the problem would be a zero allowance of removal of any vegetation inside the campground and a mandatory fine for doing so. We love Mammoth CG and like it to stay beautiful for as long as possible.
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#123
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AQI Levels
0-50 Good
Air quality is satisfactory, and air pollution poses little or no risk.
51-100 Moderate
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101-150 Unhealthy for Sensitive Groups
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151-200 Unhealthy
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201-300 Very Unhealthy
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300+ Hazardous
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