distance along equator
Thus, its diameter at the Equator is 26.5 miles (42.7 km) larger the polar diameter of 7,899.80 miles (12,713.5 km). Like its diameter, the Earth's circumference is also slightly larger at the Equator because of the equatorial bulge. For example, at the poles the circumference is 24,859.82 miles (40,008 km) but at the equator it is 24,901.55 miles (40,075.16 km). In addition, because the Earth is an oblate spheroid and it is larger at the Equator, it also rotates faster on its axis there than anywhere else.