Last year, 25-year-old Ben McDonald died suddenly of a heart attack at the finish line of the Cardiff Half Marathon.
Amongst the 27,500 runners racing through the city, Ben's family decided to walk the route in his memory.
Ben's mother, Ruth, said they entered the race this year as they didn't know how else to get through the day.
After Ben's death, his family chose to support the work of Welsh Hearts, who strive to install defibrillators and to offer heart screenings all across Wales.
The day before the half marathon, Ben's family and Welsh Hearts organised a heart screening for people between the ages of eight and 45 at Ben’s old school St Cyres in Penarth.
People of all ages came to be screened and donate money to the cause.
Ben had no history of any heart disease and he was fit and healthy, but hundreds die every year unnecessarily due to undetected heart defects.