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Western Hemisphere
geography
News •
Archaeologists discover the oldest dwelling in the Western Hemisphere at a 13,800-year-old site in Alaska
• Oct. 16, 2026, 3:00 AM ET (Live Science)
Western Hemisphere, part of Earth comprising North and South America and the surrounding waters. Longitudes 20° W and 160° E are often considered its boundaries. Some geographers, however, define the Western Hemisphere as being the half of Earth that lies west of the Greenwich meridian (prime meridian, 0° longitude) continuing to the 180th meridian. According to this scheme, the Western Hemisphere includes not only North and South America but also portions of Africa, Europe, Antarctica, and Asia.
The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Jeff Wallenfeldt.
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