Great Hikes In The National Parks

With summer nearly officially upon us, it is time to hit the trail and go for a hike. And what better place to hike than inside a national park? With that in mind, National Geographic Adventure has compiled a list of the 20 best hikes in the national parks, with some fantastic options for those looking to explore those great destinations on foot.
Amongst the trails that get a nod are Teton Crest Trail in Grand Tetons National Park, Wyoming. Called the "signature hike" of the Grand Tetons, this one takes six days to complete, covering some of the most fantastic backcountry in North America. Outer Mountain Loop Trail in Big Bend gets a well deserved nod as well, although I don't recommend that trail in the summer. Wait for the cooler autumn weather before exploring that three day hike in the Texas heat. A better warm-weather option is the Yellowstone trail from Bechler to Old Faithful. That four-day trek will take you past some of the park's amazing geysers and waterfalls.
The other 17 hikes that earn a spot on the list are spread out from Maine to Alaska and are equally impressive. They range in length and difficulty, offering up something for the experienced backpacker and beginners alike, while sharing the common thread of some of the most breathtaking scenery you could ever hope to see.
So? Did they acknowledge your favorite national park trail? What would you add to this already impressive list?