The Abyss: A Journey to the Deepest Depths of the Ocean

The ocean is unimaginably deep—far deeper than most people realize. If we were to shave off all the land from the tops of every continent and island and use it to fill the ocean’s deepest trenches, the entire planet would be covered by an ocean roughly 2 miles (3.2 kilometers) deep. Despite this theoretical evenness, three-fourths of Earth is already covered in water, and the oceans plunge far deeper than 2 miles in many places. To truly grasp the ocean's scale and depth, let’s start with some comparisons and descend step by step into its hidden, mysterious world.

The first milestone we encounter is 40 meters (131 feet) below the surface, the maximum depth allowed for recreational scuba diving. Going further, at 93 meters (305 feet), lies the wreck of the Lusitania, the famous ocean liner sunk during World War I. Remarkably, the Lusitania is 240 meters (787 feet) long, meaning it sank in waters shallower than the ship’s own length. If the wreck were positioned vertically, it would extend above the ocean’s surface. Just beyond this at 100 meters (328 feet) is where diving begins to become dangerous due to the risk of decompression sickness. Despite this danger, Herbert Nitsch set the world record for free diving by descending to an astonishing 214 meters (702 feet) on a single breath. Further still, Ahmed Gabr holds the scuba diving world record, plunging to a depth of 332 meters (1,089 feet)—almost the height of the Empire State Building.

At 500 meters (1,640 feet), we encounter the maximum dive depth of blue whales, the largest animals on the planet, as well as the operational limit of the U.S. Navy’s Seawolf-class nuclear submarine. Emperor penguins also reach their maximum diving depth here at 535 meters (1,755 feet). The pressure at this depth is extraordinary—comparable to a polar bear standing on a quarter. By 830 meters (2,723 feet), we would match the height of the Burj Khalifa, the tallest building in the world.

When we descend to 1,000 meters (3,280 feet), the ocean enters a realm of perpetual darkness, as sunlight cannot penetrate beyond this point. This zone, often referred to as the “midnight zone,” is where water pressure becomes as extreme as standing on the surface of Venus. It’s also where we encounter mysterious creatures such as the giant squid, whose existence was only confirmed in recent years. The leatherback sea turtle holds the record for deepest dive by a reptile, reaching 1,280 meters (4,200 feet). At 1,828 meters (6,000 feet), we reach the depth equivalent to the Grand Canyon’s height if it were submerged.

At 2,000 meters (6,561 feet), things start to get eerie. Here, we find creatures like the black dragonfish, a carnivorous predator with a stomach that doesn’t emit light, allowing it to remain invisible in this pitch-black environment. Descending further to 2,250 meters (7,382 feet), we meet sperm whales, known for battling colossal squids in the deep. These squids can grow up to 14 meters (46 feet) long, weigh 750 kilograms (1,650 pounds), and have razor-sharp hooks in their tentacles.

At 3,800 meters (12,467 feet), we find the wreck of the RMS Titanic. By 4,000 meters (13,123 feet), we enter the abyssal zone, where water pressure reaches an astounding 11,000 pounds per square inch. This extreme environment is home to alien-like creatures such as anglerfish, fangtooths, and viperfish. On average, the ocean floor lies at about 4,267 meters (14,000 feet), though some areas are significantly deeper.

The wreckage of the WWII battleship Bismarck lies at 4,791 meters (15,719 feet), while 6,000 meters (19,685 feet) marks the start of the hadal zone, named after the Greek underworld, Hades. Here, water pressure reaches unimaginable levels—equivalent to an elephant balancing on a postage stamp or the weight of 50 Boeing 747s on a single person. Only specialized submersibles can survive at this depth, such as the DSV Alvin, which helped explore the Titanic wreckage and can dive as deep as 6,500 meters (21,325 feet).

At 8,848 meters (29,029 feet), we reach the height of Mount Everest, were it submerged upside down in the ocean. Beyond that, at 10,898 meters (35,755 feet), filmmaker James Cameron descended in 2012 during the Deepsea Challenger mission. However, the deepest part of the ocean ever reached by humans was in 1960, when Don Walsh and Jacques Piccard descended to 10,916 meters (35,814 feet) in the Trieste submersible. Their descent took five hours, but they could only stay at the bottom for 20 minutes due to a cracked window.

At 10,994 meters (36,070 feet), we arrive at the Challenger Deep, the deepest known point in the ocean, located in the Mariana Trench near Guam. For perspective, this depth is roughly the cruising altitude of a commercial airplane. While Challenger Deep is the deepest confirmed point, it is likely that even deeper parts of the ocean exist. In fact, the Sirena Deep, discovered in 1997, reaches 10,732 meters (35,151 feet), making it the second-deepest point.

Astonishingly, we have only mapped about 5% of the ocean floor, leaving 95% unexplored. With advancements in technology, it may only be a matter of time before we uncover even greater depths in this vast, mysterious abyss.