As one of the largest Parks in all of the US, one would be surprised to know that there are few trails in Denali National Park. That being said, unless otherwise posted, you are allowed to walk where you please, see what you find, and explore at your own risk. Within reason. Be respectful of the Park, and be smart. Stop by the Wilderness Access Center before you head off all ignorant and then plot your own adventure. Or… take a trail.
One of my favorite aspects of the Park is how accessible it is to all people from all walks of life. Grandma can walk an easy, wide, flat trail or Bear Grylls can disappear into the wilderness. But if you must choose a trail, may I recommend the Triple Lakes Trail. It’s near the visitor center, and fairly easy to find as there are signs pointing you there.
At 8 miles, it’s not a brisk stroll. I spent six hours on the trail, but I also have a tendency to stop and watch birds for large portions of my time. It’s also not easy, but it’s certainly not difficult either. It has one decent switchback and a lot of elevation gain and loss. But it’s fun! And a fit family could do it… but I certainly would not encourage the average cruise-bound Alaskan vacationer to try it. Watch out for bears and moose. Enjoy the scenery. It’s a splendid hike.