Christopher McCarthy, Caesar Fierro, Paul Montero and Mauricio Busquet were found Monday morning. They left at 10 a.m. Sunday and were due back by 3 p.m.
The bikers were planning to ride from Mount Wilson to the Windsor turnout. The men apparently made a wrong turn and got lost.
"The trail that they are on is over 10 miles long and it actually traverses other trails. So it's very understandable that they could just make a wrong turn at some point," said Deputy Dan Paige with the Los Angeles County Sheriff's Department.
Family and friends spent the night outside as three rescue teams searched the Angeles National forest. By the crack dawn, three helicopters were up with infrared cameras. More than 20 hours after they hit the trail, the group was discovered near Bear Canyon.
Three of the four men are cousins, and one is a family friend. They are all between the ages of 28 and 38, and all have mountain biking experience.
A round of applause and tears of relief were shared once the good news spread that the men were found safe.
"We are relieved of course and grateful to all the guys up there. They've got a hard job to do," said Steve Lazeny, the bikers' uncle.
McCarthy said he and his cousins never biked on the trail before so they were unfamiliar with it. He said they made it through the night by building a fire when they got to Bear Canyon campgrounds.
"It's difficult to explain, but there were these two wooden benches out there in the campgrounds and we had turned them over to sort of shelter us from the air. We just focused on the fire in order to keep it going," McCarthy said.