Many tour books or travel websites highlight the jewels of the United States National Park system: Yosemite, Grand Canyon, Yellowstone, Acadia, Zion, etc. Those parks are extremely popular, drawing millions of visitors each year. Yet the park system has 58 national parks. Some boast scenery and activities almost as compelling as the aforementioned titans, yet they draw relatively few visitors. Based on my own experiences at these parks, and using National Park Service visitation figures for 2009, here are the top 10 national parks people overlook.