If you started digging straight down from most places on land and could somehow bore a perfectly straight tunnel through the center of the Earth, you would almost certainly pop out in the ocean. The point directly on the opposite side of the planet from where you stand is called your antipodal point, and because roughly 71 percent of Earth’s surface is water, the odds heavily favor a watery exit. The classic answer that Americans would end up in China is, as it turns out, wildly wrong, and the real geography of antipodes is more surprising than most people expect.
Where You Would Actually Emerge
Your antipodal point is the spot on Earth’s surface diametrically opposite your location, connected by a straight line running through the planet’s center. To find it, you flip the sign of your latitude (north becomes south and vice versa) and add or subtract 180 degrees from your longitude. When you do this for most of the world’s major population centers, the results are humbling.
If you dug from anywhere in the contiguous United States, you would surface in the Indian Ocean, roughly between Madagascar and western Australia. New York City’s antipodal point is a patch of open sea southwest of Perth. Los Angeles maps to a spot in the Indian Ocean southeast of Madagascar. Chicago, Dallas, Miami, Seattle: all ocean. In fact, no major American city has an antipodal point on dry land. The “dig to China” idea, which has been a staple of childhood imagination for generations, is off by thousands of miles. China’s actual antipodes are in South America, mostly in Argentina and Chile.
Europe fares similarly. London’s opposite side is a spot in the South Pacific east of New Zealand. Paris, Berlin, and Rome all map to the southern Pacific or ocean areas near New Zealand and the Chatham Islands. Spain and Portugal are rare exceptions in the Northern Hemisphere: parts of the Iberian Peninsula are antipodal to New Zealand, meaning a digger in Madrid or Wellington could theoretically emerge on dry land. Parts of Southeast Asia, including Indonesia, the Philippines, and Malaysia, are antipodal to sections of South America, particularly Colombia, Ecuador, and Brazil. These are among the few large land-to-land antipodal pairings on the planet.
The reason most holes end in water is straightforward geometry. Only about 4 percent of Earth’s land area is directly opposite other land. The rest faces ocean. If you picked a random spot on land and dug straight through, you’d have roughly a 1-in-25 chance of hitting land on the other side.
The China Myth and Other Antipodal Misconceptions
The idea that you’d “dig to China” from the United States is so pervasive that it has its own cultural life, appearing in cartoons, children’s books, and casual conversation for well over a century. It persists partly because people tend to think of the globe as a flat map, where China looks like it’s “on the other side” of the Pacific from the U.S. But antipodal geometry doesn’t work that way. China and the United States are both in the Northern Hemisphere, so they can’t be on directly opposite sides of the planet. To be true antipodes, one location must be in the Northern Hemisphere and the other in the Southern (or both must be extremely close to the equator).
A digger in Beijing would emerge near BahÃa Blanca, Argentina. Someone in Shanghai would surface in a rural stretch of northern Argentina. A person in Mumbai would come out in the eastern Pacific Ocean, far off the coast of South America. And a digger in Tokyo would surface in the South Atlantic, east of Uruguay. The pattern holds: wherever you start in the heavily populated parts of Asia, Europe, or North America, the other end is almost always ocean or, at best, a remote stretch of South American grassland.
The 42-Minute Fall
If such a tunnel existed and you jumped in, how long would the trip take? Under idealized assumptions, the answer is about 42 minutes from one surface to the other. That figure comes from a classic physics thought experiment: a frictionless, airless tunnel through a perfectly uniform-density, non-rotating Earth. In this scenario, gravity accelerates you toward the center, and after you pass through it, gravity decelerates you at the same rate, so you arrive at the far surface with zero velocity, like a pendulum reaching the top of its swing.
That tidy number falls apart when you add real-world complications. Air resistance would be enormous, since the tunnel would contain a column of atmosphere roughly 12,700 kilometers tall, compressed to extreme densities near the center. Researchers have examined what happens when you include drag forces in the calculation and found that friction and air resistance dramatically change the transit. Under a model using realistic density data from seismology, a falling body experiencing drag forces would not reach the other side at all; it would oscillate back and forth with decreasing amplitude, eventually coming to rest at the center of the Earth.
Even the simplified 42-minute estimate assumes the Earth has uniform density, which it does not. Earth’s core is far denser than the mantle and crust above it. When you use a more realistic density profile drawn from seismological data, the gravitational acceleration you experience changes in complicated ways as you fall. Analyses of this problem have found that accounting for realistic density profiles alters the transit time and trajectory, though the constant-gravitational-acceleration model turns out to be a surprisingly decent approximation for the motion compared to the uniform-density version.
Why the Tunnel Is Impossible
The thought experiment is fun precisely because the real tunnel could never be built. The obstacles are not engineering challenges that might be solved with better technology; they are fundamental physical barriers that make the project absurd on its face.
Temperature is the first showstopper. Earth’s interior gets hotter with depth at a rate of roughly 25 to 30 degrees Celsius per kilometer in the crust, though the gradient varies by location. By the time you reach 10 or 12 kilometers down, rock temperatures approach 200°C or more. The deepest borehole ever drilled, the Kola Superdeep Borehole in Russia, reached 12.3 kilometers in 1989 and had to stop partly because temperatures hit about 180°C, far above what the drilling equipment could handle reliably. At Earth’s center, temperatures are estimated at around 5,000 to 6,000°C, comparable to the surface of the Sun.
Pressure compounds the problem. Laboratory experiments on rock behavior under conditions simulating deep crustal drilling have shown that when temperatures reach around 500°C and hydrostatic pressure around 125 megapascals, boreholes experience accelerated creep, meaning the rock slowly deforms inward and the hole collapses.p>
Then there is the matter of what you’d actually drill through. At depths of just a couple of kilometers, you risk encountering molten rock. The Iceland Deep Drilling Project learned this the hard way in 2009, when an exploratory borehole at the Krafla volcanic field had to be abandoned at a depth of only 2.1 kilometers after magma unexpectedly flowed into the hole.
Below the crust, the mantle is not liquid in the way people usually picture it, but it is a slowly flowing solid at temperatures of 1,000 to 3,700°C. Beneath the mantle, the outer core is liquid iron-nickel alloy at over 4,000°C. No known material could maintain a tunnel through these conditions. The tunnel walls would need to withstand pressures millions of times atmospheric pressure at the center, temperatures that would vaporize any structural material, and the constant inward flow of rock and metal. The concept isn’t just difficult; it is physically meaningless with any material science we can imagine.
The Deepest Holes We Have Actually Managed
Humans have barely scratched Earth’s surface. The Kola Superdeep Borehole, at 12.3 kilometers, remains the deepest penetration into the crust ever achieved, and it took nearly 20 years of intermittent drilling to get there. That depth is only about 0.2 percent of the way to Earth’s center. The borehole’s diameter at the bottom was barely wider than a dinner plate.
Other deep drilling projects have hit their own walls. The Iceland Deep Drilling Project’s encounter with magma at just 2.1 kilometers illustrates how unpredictable subsurface conditions can be, even at relatively shallow depths by geological standards.1Elsevier. Drilling into magma and the implications of the Iceland Deep Drilling Project (IDDP) for high-temperature geothermal systems worldwide Germany’s KTB borehole reached 9.1 kilometers in the 1990s. Japan, China, and other countries have pursued deep drilling programs, but none have surpassed Kola’s record. Research on the physical limits of crustal drilling suggests that borehole stability deteriorates exponentially as temperature and pressure increase, with rock deformation accelerating to the point of inevitable collapse well before reaching the mantle.2ScienceDirect (Journal of Rock Mechanics and Geotechnical Engineering). Discussion and Discovery Limit of crustal drilling depth – Section: 3. Results
The crust itself is only about 5 to 70 kilometers thick, depending on whether you’re under an ocean basin or a continent. Even reaching the mantle, the next layer down, has never been accomplished. A project called the Mohole attempted it in the early 1960s by drilling through thinner oceanic crust, but funding was cut after reaching only about 180 meters into the seafloor. More recent proposals to drill to the mantle through thin oceanic crust remain in the planning stages, but they aim for a maximum depth of perhaps 6 or 7 kilometers below the seafloor. Reaching the core, roughly 2,900 kilometers down, is not on any serious scientific agenda.
What Happens to Gravity on the Way Down
One of the more counterintuitive aspects of the thought experiment is what gravity does during the fall. At the surface, you experience the full gravitational pull of the entire planet beneath you. As you descend, the shell of rock above you no longer contributes a net gravitational pull (this is a result of shell theorem physics, where the gravity from a uniform spherical shell cancels out for anything inside it). So the effective gravitational acceleration you feel decreases as you approach the center.
At the very center of the Earth, gravity would be zero. You’d be weightless, pulled equally in every direction by the surrounding mass. This is the moment in the thought experiment where you’d be traveling the fastest, having accelerated for roughly 6,370 kilometers. Past the center, gravity pulls you back the way you came, slowing you down. In the frictionless version of the problem, you’d decelerate at exactly the rate you accelerated, arriving at the far surface at a dead stop, then begin falling back unless someone caught you.
Researchers studying this problem have modeled the fall using Earth’s actual density profile, which is far from uniform. The core is much denser than the mantle, so the relationship between depth and gravitational acceleration is not a simple straight line. One analysis found that assuming a constant gravitational acceleration throughout the fall actually gives a better approximation of the motion than the uniform-density model, which is a somewhat ironic result given that constant gravity is arguably the less physically realistic of the two simplifications.3arXiv. Gravity Tunnel Drag
Rotation, Coriolis, and the Tunnel That Curves
There’s another problem the simple thought experiment ignores: Earth rotates. At the equator, the surface moves at roughly 1,670 kilometers per hour relative to the center. If you jumped into a tunnel at the equator, you’d carry that rotational velocity with you, but the rock at different depths moves at different speeds. Deeper layers are closer to the axis of rotation and move more slowly. As you fell, your eastward velocity would be faster than the walls of the tunnel around you, so you would slam into the eastern wall. This is the Coriolis effect applied to radial motion.
A truly straight tunnel between antipodal points through the center only avoids this problem if it runs exactly along the rotation axis, meaning the entrance and exit would need to be at the North and South Poles. Any other orientation would require the tunnel to be curved slightly to accommodate the Coriolis deflection, or you’d need the tunnel walls to somehow manage the lateral forces. At typical mid-latitude locations, the deflection would be substantial and would make a free-fall transit without hitting the walls impossible without some form of guidance system.
This is why some physicists prefer the variant of the thought experiment where the tunnel runs not through the center but along a chord connecting two surface points. These “chord tunnels” have their own elegant property: in the uniform-density, frictionless model, the transit time through any chord tunnel is the same 42 minutes regardless of the chord’s length. A tunnel from New York to Los Angeles would take the same time as a tunnel from New York to London. The vehicle would dip below the surface, accelerate under gravity toward the midpoint of the chord, then decelerate as it climbed back up to the far end. In practice, the same heat, pressure, and rotation issues make these tunnels just as impossible, but the physics is appealing enough to keep the problem in textbooks.
Finding Your Own Antipodal Point
Several free online tools let you look up your antipodal point. You enter your location and the tool plots the diametrically opposite spot on a map. The results are often deflating: vast stretches of empty ocean. But a few land-to-land pairings are genuinely interesting. Northern Spain and New Zealand are near-perfect antipodes, as are parts of the Philippines and eastern Colombia. Bermuda is roughly antipodal to Perth, Australia. Hawaii’s antipode is in Botswana. Parts of Borneo map to the Amazon basin.
If you happen to live in one of these rare land-to-land pairings, some cities have made the connection into a cultural curiosity. The word “antipodes” itself has been used as a place name: the Antipodes Islands are a small group of uninhabited islets southeast of New Zealand, named because early geographers believed they were roughly opposite Greenwich, England (they’re actually closer to being opposite a spot in western France). The naming stuck regardless. In mainland geography, the relationship between Spain and New Zealand is close enough that Wellington’s antipode is in the province of Alicante, which has occasionally led to twinning proposals and cultural events between the two regions.
For the vast majority of the world’s population, though, the answer to the title question is simple and a little anticlimactic: you’d come out somewhere in the ocean, treading water very far from land, blinking in the sunlight of whatever hemisphere you’d arrived in.