Arc of the Medicine Line : mapping the world's longest undefended border across the western plains

Astronomie Amérique du Nord Histoire 19e siècle

Astronomy North America History 19th century

Astronomy Northern boundary of the United States History 19th century

Canada Boundaries United States

Canada Frontières États-Unis

Canada Relations United States

Cartographie Amérique du Nord Histoire 19e siècle

Cartography North America History 19th century

Cartography Northern boundary of the United States History 19th century

États-Unis Frontières Canada

Frontier and pioneer life High Plains (U.S.)

Frontier and pioneer life Prairie Provinces

Géomètres Canada Biographies

Géomètres États-Unis Biographies

Great Britain Relations United States

High Plains (U.S.) History 19th century

Indigenous peoples North America Government relations History 19th century

Nord-Ouest canadien Histoire 1870-1905

Northern boundary of the United States History 19th century

Northwest, Canadian History 1870-1905

Surveyors Canada Biography

Surveyors United States Biography

United States Boundaries Canada

United States Relations Canada

United States Relations Great Britain