In 1804, Prussian naturalist and author Alexander von Humboldt spent six weeks in the U.S., exchanging ideas about art, science, politics and nature with luminaries such as Thomas Jefferson and Charles Willson Peale. This exhibit examines von Humboldt’s impact on American cultural development through 100 sculptures, maps, artifacts and paintings—including Albert Bierstadt’s 1864 Valley of the Yosemite.