French marine fife-and-drum corps (mid 1700s) performs beside Missouri River at Lewis & Clark Heritage Days fest; St. Charles, Missouri

Drumsticks beat rhythm during fife-and-drum corps performance at Lewis & Clark Heritage Days festival; St. Charles, Missouri

Lewis & Clark National Historic Trail sign frames Missouri River at Indian Cave State Park on early June day; Shubert, Nebraska

Little girl delights in shadow cast by setting sun along Missouri River in Indian Cave State Park; Shubert, Nebraska

Working replica of Lewis & Clark's 55-foot keelboat sails Missouri River oxbow lake in Lewis and Clark State Park; Onawa, Iowa

Working replica of Lewis & Clark's 55-foot keelboat sails Missouri River oxbow lake in Lewis and Clark State Park; Onawa, Iowa

Soldier in coonskin cap frames colleague at tiller aboard replica of Lewis & Clark's keelboat in Lewis & Clark State Park; Onawa, Iowa

Corps of Discovery men stand at attention as sergeant barks orders near historic trail sign at L&C festival; Lewis & Clark SP, Onawa, Iowa

Mom and girl climb Spirit Mound, sacred site where Indians told Lewis & Clark hostile 18-inch-tall arrow-shooting demons lived; Vermillion, South Dakota

Woman sits gazing from hillside overlooking Missouri River just below Oahe Lake; Pierre, South Dakota

Statue of Lakota leader Sitting Bull presides over site where he was killed in 1890; Lake Oahe on Missouri River at Mobridge, South Dakota

Park guide Dakota Goodhouse near Mandan earth lodge at On-A-Slant Indian Village; Fort Abraham Lincoln State Park, North Dakota

Costumed history interpreter at gates of reconstructed Fort Mandan, Lewis and Clark's 1804-5 wintering post; Washburn, North Dakota

History interpreter Gary Anderson in enlisted men's quarters at Fort Mandan, Lewis & Clark's 1804-5 wintering post; Washburn, North Dakota

Little girl by outdoor mural depicting Lewis & Clark and Mandan Indian outside Fort Mandan in winter 1804-5; Washburn, N Dakota

Silhouette of canoe with Lewis & Clark and Sacagawea floats above rolling farmlands south of Lake Sakakawea at Beulah Bay; North Dakota

Teepees sit outside reconstructed Fort Union, built 1828 by American Fur Co near Missouri & Yellowstone River confluence; North Dakota

Last rays of sun wash across teepees near Missouri & Yellowstone River confluence at Fort Union Trading Post NHS; North Dakota

Portrait of French trader at rendezvous weekend; Fort Union Trading Post National Historic Site, North Dakota

French voyageur Jeff Brown near teepees at rendezvous weekend; Fort Union Trading Post National Historic Site, North Dakota

Indian man on horse talks with Indian woman amid teepees at Fort Union National Historic Site, North Dakota

Plains Indian reenactor Mike Terry, a Florida Seminole, wears Cheyenne headdress and Blackfoot regalia & clothing; Fort Union, North Dakota

Plains Indian reenactor Mike Terry in Cheyenne headdress and Blackfoot clothes rides bareback at Fort Union National Historic Site, North Dakota

Great Falls of the Missouri cascade over 80 feet with an explosion of spray on a late afternoon in June; Montana

Man splits wood as fiddler plays by fire in teepee at Corps of Discovery encampment during Lewis & Clark Festival; Great Falls, MT

Corps of Discovery reenactors pole bullboat across Missouri River from small island during Lewis & Clark Festival; Great Falls, MT

Teenage boy from Fort Belknap Indian Reservation performs traditional dance during Lewis & Clark Festival; Great Falls, Montana

Portrait of Sacagawea (aka Lareen Munroe) at Lewis and Clark Festival; Great Falls, Montana

Close-up of strings of beads like those traded with Indians in 19th century; Montana US

Two motorboats speed up Missouri River beneath towering limestone cliffs at Gates of the Mountains; Helena, Montana

Flock of sheep being herded to mountain pastures in June flows around Winnebago Vista stopped on highway; Helena, Montana

Three siblings gaze at confluence of Jefferson and Madison Rivers where Missouri River officially starts; Headwaters SP/Three Forks, Montana

View westward of Idaho from Lemhi Pass, where Lewis & Clark crossed the continental divide in August 1805 and left USA.

Trapper Peak (10,157') tallest in 200-mile Bitterroot Range, looms over Bitterroot Valley in June; Darby, Montana

Daisies fill Weippe Prairie where Lewis & Clark emerged from mountains and starvation of Lolo Trail & met Nez Perce; Weippe, Idaho

Pine tree frames spectacular sunset in western Idaho; Weippe, Idaho

Clearwater River glows pink after sunset as it flows deep and wide through hill country of western Idaho; Greer. Idaho

Palouse River flows thru deep canyon on final sprint to Snake River in east Washington near Palouse Falls, Washington

View eastward of Columbia River Gorge from Beacon Rock; North Bonneville, Washington

View from Ecola State Park of rocky isles along Cannon Beach including the Haystack, accessible by foot at low tide; Oregon

Kids play in surf along sandy beach silhouetted by golden sunset at Pacific Ocean; Fort Stevens State Park, Astoria, Oregon

Elkskin-clad ranger Greg Johnson in parade ground at Ft Clatsop, reconstruction of Lewis & Clark's 1805-6 winter post; Astoria, Oregon

Elkskin dress & cradleboard similar to Sacagawea's hang inside Fort Clatsop, Lewis & Clark's 1805-6 winter post; Astoria, Oregon

Lighthouse at Cape Disappointment, named by British sea cptn John Meares in failed search for Columbia's mouth; Fort Canby SP, WA