OZU, EHIME >> A hardy group of swimmers recently demonstrated an ancient battle-focused swimming technique in the Hiji River in Ozu.

The ancient swimming style, known as “shumeshin­denryu,” originated in the area during the 17th century as a martial art for armor-clad fighters to face enemy forces in water.

Last month, members of a local group dedicated to preserving the technique, clad in 22 pounds of armor, wielded swords and swam through the river.

The demonstration, an annual event until the pandemic hit, was the first held in three years.

In addition to the old-style swimmers, dozens of people ranging in age from 2 to 80 took part in the aquatic event, braving water temperatures of about 42 degrees Fahrenheit.