Due to a special event, on Wednesday, July 8, there will be no tours of the U.S. Capitol after 11 a.m. Emancipation Hall and Exhibition Hall in the Capitol Visitor Center will be unavailable all day. While reservations prior to 11 a.m. will be honored, same-day passes will not be available. The Capitol Visitor Center will close at noon except for individuals on official business and those going to the House and Senate Galleries.

Exhibit Theme

Surveying the Mexican Border

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Boundary between the United States...
Image Caption

Boundary between the United States and Mexico, map by William H. Emory, 1855

Between 1849 and 1857, the Army Corps of Topographical Engineers marked and mapped the U.S.-Mexico boundary and published a report on natural features of the borderland. The vast new western territories immediately became a focus of congressional dispute regarding slavery in new states. This map shows the border between New Mexico and Chihuahua, Mexico.

Geography and Map Division, Library of Congress