Its base is wider than France. And it's on Mars.
Its base is wider than France. And it's on Mars.
Olympus Mons is the tallest volcano anywhere in the solar system — rising about 22 kilometres above the Martian surface. That's roughly two and a half Mount Everests stacked on top of each other.
But the height almost isn't the strangest part. Stretch its base across a map of Europe and it swallows a whole country whole. Six hundred kilometres across, edge to edge.
How does a volcano even get that big? Mars has two things working in its favour: low gravity, and no tectonic plates. On Earth, plates slowly drift and spread a volcano's energy around. On Mars, the crust just sits still — so lava piles up in the same spot, over billions of years, building something almost too large to picture.
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