"Captain Lewis and Clark holding a council with the Indians," from the Gass journals, 1810.

"Captain Lewis and Clark holding a council with the Indians," from the Gass journals, 1810 Courtesy Library of Congress, LC-USZ62-17372

Captain William Clark, c. 1810.

Captain William Clark, c. 1810 Courtesy Oreg. Hist. Soc. Research Lib., OrHi97395

Lewis's branding iron.

Lewis's branding iron Courtesy Oreg. Hist. Soc. Research Lib., OrHi104345

"A canoe striking a tree," from the Gass journals, 1810.

"A canoe striking a tree," from the Gass journals, 1810 Courtesy Library of Congress, LC-USZ62_19232

Replica of Fort Clatsop.

Replica of Fort Clatsop Courtesy Oreg. Hist. Soc. Research Lib., OrHi100550

A page from David Thompson's survey journal, dated May 9, 1811.

Fort Vancouver, 1854.

Fort Vancouver, 1854 Courtesy Oreg. Hist. Soc. Research Lib., CN008519

Map of the Fort Vancouver area during HBC period, 1824-1846.

Map of the Fort Vancouver area during HBC period, 1824-1846 Courtesy National Park Service

Sketch of Fort Vancouver by H.J. Warre, c. 1845.

Sketch of Fort Vancouver by H.J. Warre, c. 1845 Courtesy Oreg. Hist. Soc. Research Lib., OrHi83437