This race offers the only chance athletes have to swim in the calm, protected Oceanside Harbor, where water temperatures in early spring are usually in the low to mid 60's.

The bike course takes cyclists along the California coastline to San Clemente, before dropping down into the Marine Corps Base Camp Pendleton. Here, challenging hills confront athletes before they swing back to the Oceanside Harbor.

The run portion takes athletes on a winding journey out to Oceanside's flat beachfront path known as "The Strand," where miles of sandy beaches provide a beautiful and distracting vista. Runners then turn into a residential area before looping back out for a grand finish at the ocean's edge and a chute lined with energetic spectators.

More than half of the race volunteers come from units at Marine Corps Base Camp Pendleton. The presence of so many men and women serving in the U.S. Marine Corps is always a source of pride for race participants.

The 2017 IRONMAN 70.3 Oceanside offers 50 qualifying slots for the 2017 IRONMAN 70.3 World Championship in Chattanooga, Tennessee.