Famed swimmer Cho Oh-ryun and his two sons on Friday began a 120-kilometer swim to the Dokdo islets on the East Sea from nearby Ulleung Island.

Cho and his sons Seong-ung and national swim team member Seong-mo will each swim for an hour and then alternate to finish their journey in an estimated 24 hours.

Sports channel MBC ESPN is airing the event live to commemorate the 60th anniversary of liberation.

Winning two gold medals in the Asian Games in the early 1970s, Cho said he chose Dokdo as his destination as a symbolic protest against Japan’s territorial claim to the islets.