Each year, truck drivers rack up almost 400 billion miles transporting goods across the United States.
Now, truckers are putting those miles to good use by participating in an initiative to stop human trafficking.
"They're the eyes and ears of our nation's highways. They see things that we don't," Kylla Leeburg, with Truckers Against Trafficking, said.
"They're out on those lots, spending the night when they're on a long haul so they're able to capitalize on those moments," she explained.
Many drivers, like Chris Peggins, are willing and able to call authorities when they notice a young girl or woman who might be trafficked.
"I think it's wrong," he said. "People are not slaves. Slavery is over with."
At least one teenage victim has gone public thanking the truck driver who saved her. The man called authorities after spotting the girl and her cousin at a truck stop.
"If it wasn't for him calling the police and saying she just doesn't look right there, I have no idea what would have happened," the victim's mother said.
"The truck driver, the one who made the phone call, I think about him all the time," she added. "I don't know who he is, but I owe him a lot."
Truck stops are often an easy place for traffickers to operate. The predators can kidnap a woman, assault her, then drop her off at truck stops every night, forcing her to meet a quota of customers.
Truckers Against Trafficking wants to help more truckers understand the horror that's often right in front of them.
"They were seeing girls out on the lots," Leeburg said.
She added that many truckers would think nothing of it, even becoming irritated at times because girls would interrupt them while they're sleeping.
But with education, Leeburg feels truckers understand that their annoyance can be someone else's bondage.
"What they started to see once they were learning about human trafficking is that those knocks might be desperation," she continued.
Now, the group works with the trucking industry to spread the word. Their message: if you see something suspicious, call the national trafficking hotline at 1-888-373-7888.
"We're already seeing hundreds of calls coming into the hotline and investigations are underway," Brad Riley, founder of the anti-trafficking group iEmpathize, said.
The hope is that with increased awareness and involvement, truckers can become a force in shutting down the modern-day slavery taking place right on the nation's highways.