Kanakuri Shizō is regarded as the Father of marathon running in Japan, although Grandfather may be a more appropriate title. Having travelled for 18 days to compete in the 1912 Stockholm Olympics, he collapsed during his race and crept back to Japan without notifying anyone. Finding him alive and well in 1967, he was invited to finish the race by Swedish TV. During the 54 years and over 8 months it took to finish, he had gained a whole family, including 10 grandchildren.
More information:
todayifoundout.com/curious-case-olympic-marathon-run/