Yellowstone National Park is so large its boundaries span three states. Though road maps and GPS can help you from becoming completely lost, you still have to be careful traveling on a road not designed for your particular RV.

To make things easier we mapped out some of the best routes for RVs, so that you can spend more time enjoying the scenery and less time trying to figure out the many twists and turns within Yellowstone’s borders.

The Park
Mention Yellowstone and the first thoughts that come to mind are bears and Old Faithful. While Old Faithful is certainly the most popular attraction in Yellowstone, it’s merely one element of a huge thermal area. In fact, one fourth of the world’s geysers are found in Yellowstone. But, the park is much more than geysers, hot springs, and boiling mud pots. Yellowstone Lake is the largest mountain lake in the United States.

Snow runoff feeds the lake and a number of streams and rivers, which flow into the lower areas. These valleys are host to a plethora of fauna, including bison, elk, grizzly bears, bighorn sheep, and more than 100 different species of birds. Anyone who has stood at the brink of the Yellowstone River’s 308-foot-tall Lower Falls will never forget the view down the Grand Canyon of the Yellowstone.

How Big Is It?
Yellowstone encompasses more than 2.2-million acres. Mostly in Wyoming, it overflows into Montana and Idaho. In 1891, the Army Corps of Engineers constructed Yellowstone’s roads in a figure-eight pattern. Today’s roads basically follow those same routes and are known as the Grand Loop, which is 154 miles long.

Five spur roads also serve as entrances to afford visitor access from different areas of the country. The terrain varies greatly between these entrances. The interior roads have undergone extensive remodeling in recent years, making them more RV friendly.

North Entrance
The north entrance connects Yellowstone to Interstate 90 at Livingston, Montana, via U.S. Route 89. This 56-mile drive follows the old Yellowstone Road, which was the original entrance to the park, connecting to the gateway community of Gardiner, Montana. This route travels alongside the Yellowstone River and is an easy drive for RVs with no steep grades, switchback curves, or steep drop-offs. The downside is that it’s also the least scenic. RVers who choose this route will undoubtedly stay at one of two full service private campgrounds in Gardiner or at the no services NPS campground at Mammoth.

West Entrance
The west entrance connects the park to the popular town of West Yellowstone, which has a number of private campgrounds, as well as dining, shopping, museums, and more. It’s located right on the park’s border.

Bozeman is a 75-mile scenic drive to the north on U.S. Route 191. Its grades are slight and the road is fairly straight.

If you head west on U.S. Route 20, you’ll arrive at Island Park, Idaho, in another 20 miles. The only serious grade here is Targhee Pass, but it’s long so the angle isn’t that bad. Island Park is a different twist, because it’s away from the busier scene in West Yellowstone, yet is in the middle of its own pristine wilderness.

Continuing south on U.S 20 for another 52 miles will eventually connect you to Interstate 15, the Snake River Valley, and Boise via Interstate 86 or continue down I-15 to Salt Lake City.

South Entrance
The south entrance connects the park directly to its sibling to the south, Grand Teton National Park. Leaving the Grand Loop at Grant Village, this road stretches to the John D. Rockefeller Parkway in Grand Teton National Park. It climbs through forests and crosses the Continental Divide three times before reaching Lewis Lake and eventually the park border. There are numerous grades, but they are short and you won’t have any problems handling them with an RV.