Biggest thing to ever move: Many-lived story of Seawise Giant

Humanity has always loved going big. From pyramids and walls to orbiting space stations, we’ve never missed a chance to leave behind something enormous that quietly (or not so quietly) says we were here. In the modern age, that instinct reached its absolute peak not on land or in space—but at sea.

According to a detailed recounting by SlashGear, the largest ship ever built wasn’t just massive; it lived a surprisingly dramatic life under a rotating cast of names.

The story begins in the 1970s, when Greek shipping tycoon Stavros Niarchos commissioned an ultra-large crude carrier (ULCC) that would dwarf everything else afloat. Built by Sumitomo Heavy Industries at Japan’s Oppama shipyard, the vessel was initially known simply as the Oppama.

What happened next is murky, depending on the source: Niarchos may have defaulted, gone bankrupt, rejected the ship over vibration issues, or walked away after the oil shipping market collapsed. Whatever the truth, the unfinished giant was sold off before it ever entered service.

In 1979, Hong Kong shipping magnate C.Y. Tung of Orient Overseas Container Line (OOCL) purchased the ship and made it even bigger. When it finally launched in 1981, it bore the name Seawise Giant—and it more than lived up to it. From bow to stern, the tanker stretched an astonishing 1,504 feet, longer than four football fields and taller (if stood upright) than the Empire State Building. Even modern giants like the MSC Irina fall hundreds of feet short by comparison.

As SlashGear notes, the scale was almost absurd. The deck covered nearly 340,000 square feet, large enough that crew members used bicycles to get around. Its 46 tanks could carry more than four million barrels of crude oil in a single voyage. Fully loaded, it took nearly six miles to stop and more than two miles to turn. Individual components were colossal too: a 230-ton rudder, a 50-ton propeller, and anchor chain links heavier than a car.

But size came with trade-offs. The Seawise Giant was simply too large to pass through critical maritime chokepoints like the Suez or Panama Canals or even the English Channel. Instead, it lumbered around the Cape of Good Hope at a modest top speed of 16 knots, prioritising capacity over agility in a world hungry for oil.

In 1988, during the Iran-Iraq War, the ship was struck by Iraqi missiles in the Strait of Hormuz and sunk in shallow water. OOCL declared it a total loss. Yet the story didn’t end there. A Norwegian firm salvaged and rebuilt the tanker, renaming it Happy Giant. Soon after, it was sold again, becoming the Jahre Viking and returning to service for another decade.

By the early 2000s, shipping economics had shifted. Massive, slow tankers fell out of favour, and in 2004 the ship was converted into a floating storage and offloading unit. Renamed Knock Nevis, it spent its final working years anchored at the Qatar Al Shaheen oil field.

In 2009, the world’s largest moving object met its end at a ship-breaking yard in Gujarat, India. Renamed one last time—Mont—it took 18,000 workers over a year to dismantle. Today, only its 36-ton anchor survives, on display at the Hong Kong Maritime Museum, a quiet reminder of just how far “going big” once went.

By Sabina Mammadli