World's Largest Wooden Architectural Structure, world record on Yumeshima Island, Japan

May 5, 2025

Yumeshima Island, Osaka, Japan--Constructed for the ongoing Osaka 2025 Expo in Japan by Sou Fujimoto Architects, "The Grand Ring", a huge 2 km (1.2 miles) circular wooden walkway is approximately 30 meters wide (98 ft) with an outer diameter of 675 meters (2,214 ft), setting the new world record for being the World's Largest Wooden Architectural Structure, according to the WORLD RECORD ACADEMY.

"The Grand Ring, a huge 2 km (1.2 miles) circular wooden walkway, showcases innovative engineering and design. Constructed for the ongoing Osaka 2025 Expo in Japan, it serves as a key feature of the event. Notably, Guinness World Records recognized it as the planet’s “largest wooden architectural structure” on March 4, 2025," the Interesting Engineering reports.

"The colossal wooden walkway loop was constructed by Sou Fujimoto Architects. The Grand Ring is constructed primarily from local Japanese cedar and cypress, with some imported Scots pine. This massive wooden structure is approximately 30 meters wide (98 ft) with an outer diameter of 675 meters (2,214 ft).

"Moreover, it features a 12-meter-high (40 ft) “Sky Walk” adorned with flowers, providing exceptional views of the Expo and its surroundings."

"The largest wooden architectural structure is the Grand Ring which measures 61,035.55 m² (656,981 ft² 28 in²) and was achieved by the Japan Association for the 2025 World Exposition (Japan) on Yumeshima Island, Osaka, Japan, on 4 March 2025," the Guinness World Records says.

"The wooden structure is called the Grand Ring and is the symbolic architecture of the 2025 Word Exposition venue."

"The world’s largest wooden structure, the Grand Ring, has now been completed. This impressive architectural feat forms a huge circular loop, featuring a walkway that runs along its top." the Yanko Design reports.

"Measuring approximately 2 kilometers (1.2 miles) in circumference, the Grand Ring stands out as a remarkable new landmark. It was created specifically for the Osaka 2025 Expo, an event currently taking place in Japan.

"The design comes from Sou Fujimoto Architects, who are renowned for their innovative and creative approach to architecture. The Grand Ring serves as both an attraction and a functional space for visitors."

"The world's largest wooden structure has been completed. Aptly named the Grand Ring, it takes the form of a massive circular loop with a walkway on top and has a circumference of approximately 2 km (1.2 miles)," the New Atlas says.

"It was constructed using both modern techniques and Nuki joints, which is a traditional Japanese method that's used to connect wood without using nails or screws. Most of the wood used is local cypress and cedar, but some is Scots pine.

"It has been officially certified as the world's largest wooden structure by the Guinness World Records and has a width of 30 m (98 ft), plus an outer edge diameter of roughly 675 m (2,214 ft). It encircles the Expo site and is topped by a walkway called the Sky Walk at a height of 12 m (40 ft). This is lined with a large amount of flowers and allows people to stroll on top and take in views of the many pavilions and of the surrounding area."

"The Grand Ring of the world's fair was recognized as the “largest wooden architectural structure” in the world by Guinness World Records on March 4. Designed to be the iconic architectural feature of the expo, the Grand Ring’s wooden roof covers an area of 61,035.55 square meters," The Asahi Shimbun reports.

"Construction of the Grand Ring began in June 2023 and was completed on Feb. 27, 2025. The project was led mainly by the construction firms Obayashi Corp., Shimizu Corp. and Takenaka Corp. The ring stands 12 to 20 meters tall, is 30 meters wide and has an outer diameter of around 675 meters.

"Built at a cost of 34.4 billion yen ($230 million), the structure remains a topic of debate. Discussions about its significance and whether it should be preserved or repurposed after the event are ongoing. The ring was originally set to be dismantled and its materials repurposed after the expo closes on Oct. 13. However, redevelopment plans for the site now include preserving part of the structure."

Photos: World's Largest Wooden Architectural Structure, world record on Yumeshima Island, Japan
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