Reading Multisport Magazine (Vic) I kept seeing a reference to 70.3 in relation to triathlons, but couldn’t work out what it stood for.
Google helped me with a Wikipedia link to Ironman 70.3
The “70.3” refers to the total distance in miles (113.0 km) covered in the race, consisting of a 1.2-mile (1.9 km) swim, a 56-mile (90 km) bike ride, and a 13.1-mile (21.1 km) run. Each distance of the swim, bike, and run segments is half the distance of that segment in an Ironman triathlon.
It’s half an Ironman.