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 colossal wooden walkway loop was constructed by Sou Fujimoto Architects.

“It serves as the main route of visitor traffic around the Expo site, enabling smooth movement around the site and offering visitors a comfortable space sheltered from the wind, rain, and sunlight,” noted the website of Expo, which is a six-month-long world expo held in Osaka, Kansai.

The inner view of the colossal wooden structure. Osaka Expo 2025

The inner view of the colossal wooden structure. Osaka Expo 2025

Made using traditional Japanese technique

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 construction of the Grand Ring ingeniously combines contemporary building methods with the time-honored Japanese technique of Nuki joints. Interestingly, this Nuki technique is widely used in Japanese shrines and temples. 

This traditional method allows for the connection of the wooden elements without the use of nails or screws, showcasing a harmonious blend of innovation and heritage in its creation. 

“The Grand Ring is the symbol of Expo 2025 Osaka, Kansai, Japan and expresses the concept of “Unity in Diversity,” the Expo noted.

Main artery for visitor flow

The Grand Ring acts as the main artery for visitor flow. Throughout the Expo, it will ensure smooth movement across the entire Expo site.

Moreover, its sheltered design will keep the visitors protected from the weather conditions.

Initially conceived for straightforward dismantling after the Osaka 2025 Expo concludes on October 13th, the future of the Grand Ring is now under consideration.

Japanese authorities are exploring the possibility of its permanent retention and are actively seeking suggestions from residents regarding potential long-term uses.

The New Atlas reported that this approach echoes the history of Paris’ renowned Eiffel Tower, which, despite its original temporary designation for an expo, has become an enduring global icon.

The Grand Ring stands as a powerful example of a growing global wooden trend of creating large-scale timber structures.

From the expansive 9-acre roof of Portland’s airport to the soaring heights of the world’s tallest wooden skyscraper in Milwaukee, timber is proving to be a sustainable and versatile material for monumental projects.

On April 7, 2025, “A Synchronization of Air and Water” at the Expo’s Water Plaza was recognized by Guinness World Records as the “largest interactive fountain feature.”

“Water shoots up from about 300 fountains in response to people’s gestures and hands, giving visitors a spectacular experience of controlling the fountains. Watching the fountains rise in various patterns depending on the movements of your body will give you a mysterious feeling, as if you were a magician,” the Expo press release noted.

AloJapan.com