Everest is 8.8 km tall and thousands of people have stood on top of it.Olympus Mons is 25 km tall, and nobody has been anywhere near it. Its base covers roughly the same area as the state of Arizona, making it the largest mountain in the Solar System by a wide margin.Climbing it would be nothing like climbing Everest, and some of the differences work in your favor.Reaching Everest’s summit demands excellent physical condition and weeks of acclimatizing to thin air at extreme altitude. It’s brutal and people die attempting it every year.Olympus Mons has an entirely different set of problems, starting with the obvious one. You’d have to get to Mars first.Assume that’s handled and you arrive at the base, where a giant moat encircles the mountain, formed by the sheer weight of the volcano pressing down on the crust.Check the weather before you start. Fierce windstorms tend to rage across the planet, though the thin Martian atmosphere means they hit with far less force than equivalent winds on Earth.The atmosphere gives you another advantage too.It’s almost entirely carbon dioxide, which means you’re wearing a spacesuit feeding you a steady oxygen supply regardless of altitude. No acclimatization needed at any point on the climb.That removes the single deadliest feature of Everest. Above 7.9 km sits what climbers call the death zone, where oxygen levels drop critically low and the human body starts breaking down. At the summit you’re breathing a third of the oxygen available at sea level.On Olympus Mons, you just walk to the top.The practical challenge is carrying enough air, which is why you’d want a compact device converting carbon dioxide into oxygen rather than hauling tanks up 25 kilometers.Then comes the first leg, and it’s the worst part of the entire climb.The journey opens with a nearly vertical cliff somewhere between 7 and 10 km high depending on your approach. That’s roughly a Mount Everest standing on end, before the actual mountain begins.Survive that and the rest is surprisingly gentle. Around 30 hours of continuous hiking to the summit, on a slope so gradual it barely registers as climbing.You’d be doing all of it inside a spacesuit weighing about 38 kg.That figure already accounts for Martian gravity being roughly a third of ours. The same suit on Earth would weigh close to 100 kg, so picture attempting Everest carrying that.Everything keeping you alive is inside it. Oxygen, food, water, and no option to take it off at any point.Which makes eating awkward. Astronauts on spacewalks manage with rice paper covered fruit and cereal bars, designed to be eaten in a single bite so no crumbs escape into the helmet.Water has to travel inside the suit too, or in a temperature controlled backpack, because average temperatures on Mars sit at minus 62 degrees Celsius and anything exposed freezes fast.And yes, you’d be wearing a thick absorbent diaper for the full 30 hours.Near the summit, something unexpected happens. You’d pass through thin wispy clouds of water vapor, which seems impossible on a planet where it never rains.Then you reach the top, and the view is genuinely staggering.A collapsed crater 85 km wide opens up in front of you, roughly the width of Lake Ontario. The atmosphere is so thin around you that it feels less like standing on a mountain and more like standing on an island floating in space, with a rust colored sea stretching to the horizon in every direction.You made it. First person ever to stand on the highest point in the Solar System.Now all you have to do is climb back down, and then work out how to get home. Which you probably should have planned before leaving.Hope you’re comfortable on Mars, because you might be there a while.