2006 39c Yosemite Falls, Tallest Falls

2006 39c Rocky Mtns, Largest Mtn. Chain

2006 39c Peregrine Falcon, Fastest Bird

2006 39c Grand Canyon, Largest Canyon

2006 39c Oroville Dam, Tallest Dam

2006 39c FL Coral Reef, Longest Reef

2006 39c Steamboat, Tallest Geyser

2006 39c Bristlecone Pines, Oldest Trees

2006 39c Coast Redwoods, Tallest Trees

2006 39c Mammoth Cave, Longest Cave

2006 39c Rainbow, Lrg. Natural Bridge

2006 39c Cornish-Windsor Bridge, Longest

2006 39c Longest Hiking Trail

2006 39c Crater Lake, Deepest Lake

2006 39c Lake Superior, Largest Lake

2006 39c Mississippi River,Largest Delta

2006 39c MS-MO River, Longest River Sys,

2006 39c Kilauea, Most Active Volcano