document: 29 December 2016 Last updated at 18:10 GMT
  Ryan Holmes, 21, has covered more than 2,500 miles so far, running an average of two races a week.
  His efforts have also raised thousands for Cancer Research in honour of a good friend who is suffering from myeloma.
  "It's been challenging at times but it's been a good journey," he told BBC South East Today.
summary: A Whitstable man is aiming to become the youngest person to run 100 marathons when he completes a race in Deal on New Year's Eve.