Answer: Chimborazo, Ecuador

Most of the time we measure the height of mountain peaks from sea level. Sometimes we mix it up a little and measure their height from the continental shelf and every now and then you can even argue over which peak is the highest if you measure from the depths of the sea floor.

While measuring in the aforementioned fashions certainly will give you more than a few high peaks to admire, there’s one particular peak that often goes overlooked because it’s only the tallest in the world if you measure with a rather unconventional measuring stick: distance from the very center of the Earth.

Thanks to the phenomenon of equatorial bulge, wherein the equator of planets bulge slightly outward due to the centrifugal forces generated by the rotation of the planet, any mountains on or near the equator get a bit of a boost. Thanks to this boost the dormant stratovolcano Chimborazo, found in the portion of the Andes mountain range passing through central Ecuador, isn’t the highest peak when measured from sea level (at mere 20,564 feet), but when measured from the center of the Earth it has the highest elevation of any point on Earth’s surface.

What’s fascinating about the whole distance-from-the-center-of-the-Earth business is that because Chimborazo sits almost directly on the equator (it is only one degree off), the boost it receives from equatorial bulge is so significant that despite not even being the tallest peak in the Andes range it ends up being farther from the center of the planet than any other peak on Earth, including its much taller immediate neighbors.