VOL.205 JULY 2025
EXPO 2025 OSAKA, KANSAI, JAPAN: THE CHARM OF KANSAI
‘Uzu no Michi’ Offering Close-Up Views of the Naruto Strait’s Whirlpools
View of the Onaruto Bridge spanning the Naruto Strait with the whirlpools below.
Photo: ISHIZAWA Yoji
At the Tokushima Prefecture Zone within the Kansai Pavilion at Expo 2025 Osaka, Kansai, Japan—titled Where Water Flows: Experience Tokushima with your five senses! —exhibits showcase Tokushima’s way of life in harmony with water. This section highlights the natural phenomenon of whirlpools that occur in the Naruto Strait in Tokushima Prefecture.
The Tokushima Prefecture Zone of the Kansai Pavilion at Expo 2025 Osaka, Kansai, Japan is themed Where Water Flows and consists of three areas: the Heritage Area, showcasing traditional crafts such as Awa washi (Japanese handmade paper) and Awa indigo dyeing; the Now Area, where visitors experience the Yoshino River, the Naruto Whirlpools, and Awa Odori1 through projection mapping that combines live-action footage and computer graphics; and the Future Area, which introduces Tokushima Prefecture’s initiatives toward a sustainable future.
Through exhibits that blend traditional culture and rich natural beauty with cutting-edge technology, Tokushima is sharing its approach to creating new value and leading the world toward a sustainable society. This section focuses on the Naruto Whirlpools, featured as part of the virtual tourism experience in the Now Area.
The Naruto Whirlpools are a dynamic natural phenomenon where powerful tidal currents swirl into whirlpool patterns on the surface of the Naruto Strait, located between Naruto City and Awaji Island. This unique spectacle attracts many visitors eager to witness a phenomenon not seen elsewhere, making it a popular tourist destination. We spoke with ASAHARA Keisuke, who manages and operates Onaruto Bridge Uzu no Michi about this remarkable natural wonder.
Photo: ISHIZAWA Yoji
“The Naruto Strait is located between the Seto Inland Sea2 and the Kii Channel.3 The timing of the tides differs between these two bodies of water—when one is at high tide, the other is at low tide. This difference in water levels between adjacent high and low tides creates fast tidal currents that can reach speeds of up to approximately 20 km/h. The strength of these currents ranks among the world’s three greatest tidal streams, alongside Italy’s Strait of Messina and Canada’s Seymour Narrows,” says ASAHARA.
“The whirlpools, known as the Naruto Whirlpools, are said to form due to the rotational force generated by the speed difference between the fast currents flowing through the center of the strait and the slower currents along the shore. At times, these whirlpools can reach diameters of 20 to 30 m.”
ASAHARA explains that these massive whirlpools, formed by the forces of nature, offer visitors a powerful experience. “There are several ways to enjoy the Naruto Whirlpools up close. One is from the Uzunomichi Walkway, which runs along the girder of the Onaruto Bridge4 spanning the Naruto Strait. Another is from the Uzunomichi observation room, where visitors can take in the whirlpools along with panoramic views of the Naruto Strait and the bridge itself. A third option is to board a sightseeing boat, which allows you to view the whirlpools from the water at very close range.”
Among these, Uzu no Michi offers a particularly unique experience. “Parts of the walkway and the observation room feature glass floors, allowing visitors to look directly down at the whirlpools about 45 m below,” says ASAHARA. “It’s a thrilling experience found only here—where you can simultaneously feel the power of nature and appreciate the structural beauty of the massive, sturdy bridge.”
Photo: Onaruto Bridge Uzu no Michi
On the Tokushima Prefecture side of the Onaruto Bridge, visitors will also find the Onaruto Bridge Crossing Memorial Hall EDDY, where they can enjoy learning about the bridge’s construction technology and natural phenomena like the whirlpools.
“We hope visitors will also take the opportunity to explore the history and engineering of the Onaruto Bridge, which celebrates its 40th anniversary in 2025,” says ASAHARA. He also notes an increase in visitors from abroad and highlights ongoing efforts to welcome them. “To accommodate international guests, signage is available in five languages: Japanese, English, Simplified Chinese, Traditional Chinese, and Korean. Upon request, simple guided explanations can also be provided in English or Chinese. Surrounding facilities, such as the museum and whirlpool sightseeing boats, are also expanding multilingual support, including English and Traditional Chinese, so visitors can feel at ease when they come.”
In addition to the Naruto Whirlpools featured in this article, ASAHARA explains that Tokushima Prefecture is also known for its rich local culture rooted in daily life, such as traditional crafts, including Aizome indigo dyeing5 and Awa Odori, both introduced in the Tokushima Prefecture Zone of the Kansai Pavilion. He encourages everyone to experience the charm of Tokushima Prefecture—where majestic nature and traditional culture come together—both at Expo 2025 Osaka, Kansai, Japan and in the region itself.
- 1. A traditional Bon dance held in and around Tokushima City, Tokushima Prefecture. Bon is a festival held once a year where the spirits of ancestors are welcomed back to this world, entertained, and then sent off again. The largest event, Tokushima City’s Awa Odori, takes place annually from August 11 to 15. (See: Tourism Providing Experience of Awa Culture | October 2023 | Highlighting Japan)
- 2. Japan’s only inland sea, surrounded by 11 prefectures in the Kinki, Chugoku, Shikoku, and Kyushu regions.
- 3. A body of water between northwestern Wakayama Prefecture and eastern Tokushima Prefecture, connecting the Pacific Ocean and the Seto Inland Sea.
- 4. A suspension bridge connecting Awaji Island in Hyogo Prefecture and Naruto City in Tokushima Prefecture. Total length: 1,629 m.
- 5. A traditional dyeing technique using indigo plants to color thread or fabric. The Yoshino River basin in northeastern Tokushima Prefecture is known as Japan’s top producer of indigo dye.
By MOROHASHI Kumiko
Photo: Onaruto Bridge Uzu no Michi; ISHIZAWA Yoji; PIXTA