NAKADOMARI, Aomori Prefecture—Conquering the Tsugaru Strait between the main island of Honshu and Hokkaido is one of the open water swimming challenges across the globe known as the Oceans Seven. 

Numerous experienced swimmers from abroad are eager to dive in and take on the strait.

However, many have been forced into a long wait due to a lack of a sufficient support system offered locally.

Now, officials in this town are preparing to accommodate international challengers with the assistance of accomplished long-distance swimmer Haruyuki Ishii, who swam the strait many times.

SWIMMING VERSION OF 7 SUMMITS

The Oceans Seven, devised in 2008, consists of seven long-distance swims across the toughest channels scattered across the globe: the English Channel between Britain and France; the North Channel between Ireland and Britain; the Strait of Gibraltar between Spain and Morocco; the Catalina Channel in California; the Moloka’i Channel in Hawaii; the Tsugaru Strait and the Cook Strait in New Zealand.

The Tsugaru Strait can be the toughest leg of all the seven swims for two reasons, according to experts.

The tidal currents there are exceptionally strong and their speed and direction keep changing constantly.

Many swimmers usually make the attempt in June and July, when the waves are calmer, water temperatures are higher and the days are longer.

It takes an average of 10 hours or so to complete the crossing.

The shortest distance between Hokkaido and Aomori Prefecture spans about 20 kilometers, a route connecting Cape Oma on the Shimokita Peninsula in the prefecture and the eastern district of Hakodate on Hokkaido.

But challengers typically end up traversing a stretch of 30 km or so due to the currents. Only half of even experienced swimmers succeed in their attempt.

Another factor that makes the strait less accessible is an absence of organized support efforts despite a growing stream of international swimmers and their teams.

In the other channels, well-developed support systems are in place, including arranging for a boat that will accompany a swimmer, conducting safety management and securing an interpreter, once the fees are paid.

In the case of the Tsugaru Strait, support in available in Japanese.

Since only private tour guides accept one or two swimmers from abroad a year, there are 100 or so international swimmers on the waiting list.

NAKADOMARI OFFERS MUCH-NEEDED SUPPORT

One such guide is Ishii, a 71-year-old resident of Tokyo, who swam the strait eight times. He is also well experienced in open water swimming in other parts of the world.

Ishii became concerned about the future of the Tsugaru Strait leg as he was unsure of how much longer he could continue to assist due to his age.

Nakadomari leaders learned about the growing popularity of channel swims when they met with their counterparts in Fukushima, a town on Hokkaido across the strait, and about Ishii’s activities.

That inspired Nakadomari officials to seek to attract marathon swimmers to their town, with a population of about 9,500, by building a support system so that they would choose the town to embark on their quest.

There are, in fact, countless possible courses to cross the Tsugaru Strait, including options to begin the attempt from the Hokkaido side. A route along the Seikan undersea tunnel is also short.

But Taku Yoshida, a Nakadomari official, is adamant that his town is the best place to start.

“To cross the strait from Honshu, swimmers should dive in the waters from Nakadomari,” he said.

Fast currents flow in the strait northeast from the Sea of Japan to the Pacific Ocean. That means challengers would have to swim against the tide if they started from Hokkaido.

And to take advantage of the northeasterly tidal currents, a site farther west in the prefecture is better.

The spot that fits the bill best is Cape Gongen in Nakadomari on the Tsugaru Peninsula in the western part of the prefecture. If a swimmer starts there, they can reach the shores of Fukushima town in Hokkaido, riding on the currents. 

“We happen to be in a good position geographically and all we need to do is to make the best use of it,” Yoshida said.

Nakadomari employees have begun to learn the ins and outs of offering support by accompanying Ishii when he is offering assistance.

In June, when a Chilean woman in her 30s swam the strait, town employees embarked in a fishing boat that sailed alongside her.

The woman finally made it to the shores of Hokkaido about 11 hours after she began the challenge. There was a time she made no progress as she was held back by the swift currents.

The town plans to support several more international swimmers before it sets up a dedicated task force in autumn.

Next year, the town will offer assistance to eight swimmers, most of them from overseas requesting Ishii’s services.

The town’s effort to better accommodate marathon swimmers is welcomed by local residents.

Swimmers and their teams are expected to stay in Nakadomari for several days after they arrive and wait for a day when weather conditions are suitable to attempt a crossing. They will likely stay a few more days after their swim.

Operators of lodgings, restaurants and rental boats escorting them will likely see a boost in business through their patronage.

Many renowned long-distance swimmers are actively sharing their thoughts about their challenges and their stays through social media, likely raising the town's international profile.

“Nakadomari is not as famous as nearby sightseeing spots such as Goshogawara and Cape Tappi, but international visitors may come to my establishment when the town becomes popular,” said an operator of an izakaya pub in Nakadomari. 

Yoshida noted the importance of incorporating safeguards to better respond to emergencies by working with maritime officials.

“We want to welcome swimmers with a setup to prevent accidents while learning from Ishii,” he said.