For 21 years its been a part of the pre-race activities at the Ironman World Championship. The annual Underpants Run is a mainstay of race week.

The Parade of Nations signals the arrival of athletes from around the world ready to compete at the Ironman World Championship. This year's race features 2,500 athletes from 82 different countries.

The sold out Hoala Swim, an opportunity to swim the Ironman World Championship course, provided some interesting insights on next week's race.

Andreas Böcherer and Daniela Sämmler put Germany on the top of both podiums and nailed their Kona slots at Ironman Germany, while Alex Zinardi continued his amazing multisport achievements. A look at the day in pictures.

Elliot Smales and India Lee took what started out as a very wet day at Ironman 70.3 Weymouth, where the swim had to be shortened due to the choppy conditions. A look at race day in pictures.

Belgium's Timothy Van Houtem and Great Britain's Laura Siddall were the class of the fields at the ETU Long Distance Championship held at Challenge Madrid.

American Rodolphe Von Berg and France's Manon Genet took Ironman 70.3 Nice, a dress rehearsal for next year's Ironman 70.3 world championship.

Florian Angert took the day over Ironman world champion Patrick Lange, while Laura Philipp dominated the women's race. Photos from Ironman 70.3 Rügen.

Europe's oldest triathlon has a rich tradition of hard racing and an outstanding atmosphere. Pictures to prove it from Challenge Almere-Amsterdam 2018.

A look at Challenge Walchsee where Sebastian Kienle nailed his final tune-up for Kona and Eva Wutti became the first Austrian to win the event.

With two former champions, two Olympic gold medalists and a plethora of world titles between them, Jan Frodeno, Javier Gomez and Alistair Brownlee put on quite a show at the Ironman 70.3 World Championship. The day in pictures.

After snowy conditions forced the cancellation of the bike, Ironman 70.3 Zell am See-Kaprun became a swim-run event. A look at the day that still included some spectacular scenery in pictures.

Renowned as a spa destination, Vichy hosted a fast 70.3 race won by Maurice Clavel and Helle Frederiksen. Ironman 70.3 Vichy 2018 in pictures.

Mario Mola mastered the run yet again as he captured the ITU World Triathlon Montreal in impressive style. The day in pictures.

With steep climbs and scenic views from a course that winds through farms and spectacular countryside, the Allgäu Triathlon has been an iconic stop on the German triathlon scene for 36 years. Photos from this year's race.

Set in the spectacular Laurentians, Ironman Mont-Tremblant is a one of a kind event that offers amazing scenery, hospitality and fast racing. Photos from the record-setting day.

Sebastian Kienle arrived as the prohibitive men's favorite and delivered an impressive performance at Challenge Turku. Sarah Lewis topped the women's field. A photo gallery from the spectacular race in Finland.

The 16th running of the epic Norseman Xtreme Triathlon continued the event's long history as one of the most challenging triathlon races on the planet. Photos from this year's race.

For most triathletes, it is the dream of a lifetime - qualifying for the Ironman World Championship. For these Kona-bound competitors, its a dream come true.

Daniela Sämmler and Sarah Crowley ripped through the flat, fast bike course at Ironman Hamburg in just over four and a half hours, while James Cunnama and Bart Aernouts finished in just seconds over four hours. Photos from the super-fast rides in Germany.

Heather Jackson led from start to finish to take the women's-only pro race at Ironman Lake Placid. TriathlonWorld.com recaps the day's racing in pictues. (Results on final slide.)

France led the way at the ITU Triathlon Mixed Relay World Championships in Hamburg.

Cassandre Beaugrand shocked the field with a stellar run that put her clear of the rest of the field at the ITU World Triathlon Hamburg. We recap the race in pictures.

Mario Mola took his third straight ITU World Triathlon Hamburg thanks to a stellar run. The men's race in pictures.

A 3.8 km swim, 185 km bike and 42.2 km run the Ironman European Championship in Frankfurt was five km longer than a standard Ironman race, making getting to the finish line even more of an achievement.

Jan Frodeno and Daniela Ryf put on impressive pre-Kona shows as the two dominated impressive fields to take the Ironman European Championship in Frankfurt. The day in pictures.