
The Ironman World Championships have been held in Kailua-Kona, Hawaii, every year since 1978. This year's edition marked the event's 40th anniversary. More than 2000 athletes embarked on a 140.6-mile journey, putting their bodies to the ultimate test.

The course starts with the swimming stage. Athletes swim in one giant 2.4-mile loop of the harbor.

Athletes tread water while they wait for the start of the race. There are multiple categories for different age-groups and abilities.

After completing the swim, athletes then embark on a 112-mile bike ride across the scorched island.

Participants complete the event with a full marathon, running 26.2 miles in the blistering heat.

Hawaii makes for an idyllic location for the grueling event.

Temperatures in the 2018 race reached an estimated 120 degrees Fahrenheit. Athletes are provided with multiple water stops along the way.

Daniela Ryf won the women's Ironman World Championship. The Swiss athlete was stung by jellyfish during the swim but recovered to take the title.

Germany's Patrick Lange won the men's event to secure his second world title. He proposed to his girlfriend, Julia, at the finish line. She said yes...