Honda ARX1200T3DXT3 Owner's Manual page 67

Longitudes, also called meridians, are vertical
circles extended from the North Pole to the
South Pole. The zero degree longitude, which
passes through Greenwich, England, divides
the Earth into the Eastern and Western
hemispheres. The 180 degree longitude, half
way around the planet, is the international
data line.
LONGITUDE
0° longitude
(Greenwich, England)
North Pole
Western
Hemisphere
South Pole
Each longitude 69 miles wide
Each time zone equals 15° longitude
Introduction
180° longitude
(internationl data line)
Eastern
Hemisphere
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