Yellowstone National Park offers a number of Free Days. The next is August 4th, the one year anniversary of the Great American Outdoors Act. Not that I really mind paying the $35, seven-day vehicle permit. The fee equates to about $7 per-person for my carload, which seems more than fair for admission to one of our nation's greatest parks.

There is another way to get a free pass at Yellowstone Park. They shared a Tweet last week, reminding the public that if you're riding a horse or utilizing a pack mule or other stock in your park adventure, you can get a free day permit.

I don't think they mean riding up to the gate on your trusty steed.

Although, I suppose you could? I'm not horse-savvy, but I believe you would arrive at the park with your horses or pack mules on a trailer and then depart on a backcountry trail. A news release says,

Launched in 2017, the free permit system helps park managers understand where, when and how many stock users visit the park. This information is important in protecting park resources and the quality of the visitor experience in the backcountry.

Adding,

The free day ride permits provide an opportunity for park staff to assist riders in planning safe, enjoyable and low-impact trips.

They remind stock users that a backcountry permit is still required for overnight stays.

Get our free mobile app

There are currently no active forest fires in Yellowstone National Park. However, the fire danger level was upped to "HIGH" on Monday (6/21). Please be extra cautious with open flames, heat sources and cigarette butts if you're visiting the park.

LOOK: Stunning vintage photos capture the beauty of America's national parks

Today these parks are located throughout the country in 25 states and the U.S. Virgin Islands. The land encompassing them was either purchased or donated, though much of it had been inhabited by native people for thousands of years before the founding of the United States. These areas are protected and revered as educational resources about the natural world, and as spaces for exploration.

Keep scrolling for 50 vintage photos that show the beauty of America's national parks.