The Pearl Bridge: The World's Longest Span Opens
On April 5, 1998, Japan opened the Akashi Kaikyo Bridge, whose 1,991-meter central span made it the longest suspension bridge in the world.
In 1955, two ferries crossing Japan's Akashi Strait went down in a storm, killing 168 people. The disaster convinced Japan of one thing: the strait could never again depend on ferries alone.
It took decades of planning and ten years of building. Construction began in May 1988 under designer Satoshi Kashima, and on April 5, 1998, the ribbon was cut on the Akashi Kaikyo Bridge — the "Pearl Bridge" — linking the city of Kobe on Honshu with Awaji Island. Together with its sister spans, it completed a highway chain across the Inland Sea to Shikoku.
The Pearl Bridge was the centerpiece of the Honshu-Shikoku Bridge Project, a decades-long national effort that built three separate crossings over the Inland Sea — the Seto Great Bridge, the Akashi Kaikyo, and the eastern route via the Ōnaruto Bridge — finally linking the island of Shikoku to Honshu by road.
The numbers were staggering. The bridge runs 3,911 meters from shore to shore, with a central span of 1,991 meters (6,532 feet) — the longest suspension span ever built, nearly a quarter-mile beyond the previous record holder, Denmark's Great Belt Bridge. Its two steel towers rise 297 meters above the strait. Builders used some 181,400 metric tons of steel, and the main cables alone contain roughly 300,000 kilometers of wire — enough to circle the Earth more than seven times over.
The strait is one of the most violent construction sites on the planet: deep water, fierce tidal currents, typhoons, and earthquakes. Engineers built the bridge to withstand 290 km/h winds and a magnitude 8.5 quake. Then, mid-construction, the ultimate test arrived uninvited. On January 17, 1995, the Kobe earthquake struck with its epicenter almost directly between the two towers, shoving them about a meter farther apart. The deck had not yet been hung, so the flexible design simply absorbed the shift — the central span grew from a planned 1,990 meters to 1,991.
The Pearl Bridge held the world record for nearly a quarter century, until Turkey's Çanakkale Bridge opened in March 2022. It still carries six lanes of the Kobe-Awaji-Naruto Expressway across one of the world's busiest waterways, beneath which a 1,500-meter-wide shipping lane must stay open.
Why it matters: the bridge proved engineers could span the seemingly unspannable — the longest, tallest, most ambitious suspension bridge ever attempted, in a place where the earth itself moves. Every record since has been measured against it.
Photo: Tysto, public domain (via Wikimedia Commons).
