The World Has Three Different 'Tallest Mountains' — and Everest Only Wins One

Ask anyone which mountain is the tallest on Earth and they will say Mount Everest without hesitation. They are right — and also, depending on how you define ‘tallest’, completely wrong. Measure by three different, equally legitimate methods and you get three different champions: Everest, a Hawaiian volcano most of which sits underwater, and an Ecuadorian peak more than 2,500 metres shorter than Everest that nonetheless pokes deeper into space.

Everest wins the measurement everyone actually means

Highest point above sea level is the definition almost everyone has in mind, and on that one Everest is untouchable. It is the number climbers train for, pay permit fees for and risk their lives for.

That figure, 8,848.86 metres, came out of a years-long joint Chinese–Nepali resurvey completed in 2020, replacing the long-used 1955 Survey of India figure of 8,848 metres. Nepal’s negotiators had insisted the true summit height be confirmed jointly rather than taken from either country’s older data. It is the number written into Nepal’s permit paperwork and into every itinerary that ends at Everest Base Camp — itself at 5,364 metres, looking up at a summit still nearly 3.5 vertical kilometres higher.

Why a shorter mountain can win

Because sea level is a convention, not a ruler. It is a convenient human reference point measured along the geoid, Earth’s average sea-surface shape, and two other measurements ignore that convention entirely.

Both of them dethrone Everest. Neither of them is a trick question or a technicality — they are simply answers to a different question about the same planet.

Mauna Kea is taller by a kilometre, and mostly underwater

Measured from base to summit rather than from sea level, Mauna Kea beats Everest by more than a kilometre. Its trick is straightforward: it is a volcano built up from the floor of the Pacific Ocean, roughly six kilometres below the surface.

Only its top 4,207.3 metres break the waterline. Add the submerged base back in and it totals 10,211 metres from root to summit. Nothing about the mountain is hidden or disputed — the majority of it is simply in a place nobody measures from.

Chimborazo is closer to space because the Earth bulges

Chimborazo’s summit sits about 2,100 metres farther from the centre of the Earth than Everest’s, despite being 2,580 metres shorter by the sea-level yardstick. The reason is the shape of the planet rather than the size of the mountain.

Earth is not a perfect sphere. It is an oblate spheroid, bulging outward at the equator because of its own rotation: the equatorial radius of 6,378.137 km is about 21.4 km larger than the polar radius of 6,356.752 km. Chimborazo sits just over a degree south of the equator, almost exactly on that bulge, so its summit works out to roughly 6,384.4 km from the planet’s centre. Everest, tucked up near 28 degrees north where the bulge has already tapered off, sits at about 6,382.3 km. Subtract one from the other and the Ecuadorian peak wins by two kilometres of pure planetary geometry.

Which number should you actually care about

The sea-level one, because it is the only one of the three that changes how it feels to be there. Altitude above sea level is what thins the air, and thin air is the entire physical experience of the Himalaya.

Base-to-summit height and distance from the planet’s core are real measurements and genuinely interesting, but neither has any effect on a human body. You cannot feel the equatorial bulge. You can very much feel 5,364 metres.

What this means for trekkers

Nothing here changes the number that matters on the ground in Nepal. 8,848.86 metres is still the highest point a human being can stand on this planet’s surface, no asterisk needed.

For our guides in Pokhara this is mostly a good pub-quiz fact to have ready on the trail. Sea-level altitude, the measurement that actually determines how hard it is to breathe at 8,000 metres, will always be Everest’s alone. Trekkers heading into the Everest region this autumn will be looking up at the same 8,848.86 metres regardless of what is happening on a volcano in Ecuador or a seamount in the Pacific.

Source: ScienceBlog.com

Cover photo: Dick Hoskins via Pexels (Pexels License). Section photos: eberhard grossgasteiger via Pexels (Pexels licence); photowithom via Pexels (Pexels licence).