Alaska
Since 2006 I have been visiting a different place in Alaska each year, and hope to continue doing so.
2006: Wrangel/St Elias NP, Seward, and Valdez
2007: Homer and Kachemak Bay State Park
The drive from Las Vegas to southwest Utah's slot canyons, or the Grand Canyon's North Rim, takes you through a tiny section of northwest Arizona on Interstate 15. But this short section passes through the Virgin River Gorge, an impressive section of highway. I've always wanted to check it out. On my trip to the Grand Canyon I had time to stop on the way back at a place called Cedar Pocket. There are short hikes in the area, but there are also untracked wildernesses on both side of the interstate - for a future trip maybe.