Camp Pendleton World Famous Mud Run

A runner wipes mud from her eyes as she makes her way through the obstacles during the Mud Run.  (Rick Loomis / Los Angeles Times)

A mud-caked runner after the competition. For civilians, the World Famous Mud Run is a chance to get a look at Camp Pendleton, a 120,000-acre gated community not usually open to visitors. For Marines, it’s a chance to show civilians what they do. makes his way through a course of obstacles during the 21st annual World Famous Mud Run held on Saturday at Marine Corps Base Camp Pendleton. About 5,000 runners took place in the event and about 20,000 people will take part over the course of two weekends. Obstacles include tunnels, bridges, mud pits, walls and more. ( Rick Loomis / Los Angeles Times )  (Rick Loomis / Los Angeles Times)

Runners make their way through various obstacle courses during the annual World Famous Mud Run at Camp Pendleton.   (Rick Loomis / Los Angeles Times)

Runners slosh toward one of the World Famous Mud Run’s obstacles. About 5,000 civilians participated on Saturday; by the end of next weekend, about 20,000 will have navigated the 5K and 10K courses.   (Rick Loomis / Los Angeles Times)

A runner rinses off after making her way through one of the Mud Run’s courses. Obstacles included tunnels, bridges, mud pits, walls and more.  (Rick Loomis / Los Angeles Times)

Some of the Mud Run participants are weekend athletes striving for a personal best on either the 5K or 10K course. Some are members of teams from their workplaces, churches, schools or neighborhoods.   (Rick Loomis / Los Angeles Times)

“This is high-caliber mud, you can’t get this at your spa!” shouted the starter just seconds before setting off the first wave of runners. “This is Marine Corps mud!”  (Rick Loomis / Los Angeles Times)

After finishing the course, mud-caked runners were directed to outdoor showers where Marines with bullhorns provided motivation: “Hurry up, hurry up, hurry up, get out of my shower!”   (Rick Loomis / Los Angeles Times)

As mud running has increased in popularity, the Camp Pendleton event has evolved and now includes an outdoor rock concert, carnival rides and food vendors.   (Rick Loomis / Los Angeles Times)