Arriaga, Mexico(CNN) Carlos Gomez took a break last month on a potholed road in southern Mexico littered with abandoned shoes and empty water bottles. The journey's toll was etched across his face.
"I am feeling some chills," Gomez said. "I have had a fever for a few days."
The 52-year-old was among thousands of Central American migrants who entered Mexico from Guatemala last month. They've trudged along for weeks despite exhaustion and threats from the US and Mexican governments to turn back.
Here's a glimpse into the lives of those who left everything behind to make this trek to America.
Few of them have any money. Some would have gone hungry long ago if not for the generous Mexicans and municipalities that offered them tamales and pineapple juice along the route.
Many are wearing flip-flops, rubber clogs or sneakers that are falling apart.
Like others, Gomez has faced grueling heat and torrential rains. At night, the group members slept on sidewalks before waking each morning to depart again for their daily marathon.
Despite his failing health, Gomez, an out-of-work farmhand from Honduras, said he had no choice. He left behind eight children back home, and the only way to earn enough to feed them, he said, is to keep moving forward and reach the United States.
"There is no work anymore. The government took our lands," he said.
President Donald Trump has railed against the caravan and described it as an organized effort by dark forces to introduce criminals and possibly terrorists into the United States.
But after a week traveling with the group, CNN witnessed little, if any, organization.
People joined and left at will. Exhausted by the effort, many decided to return home.
Last month, the Mexican government said the caravan had shrunk from more than 7,000 migrants to about 3,600. But organizers claimed their numbers are growing.
One of the migrants, 22-year-old Oscar Rodriguez, said he wants a better life for his 2-year-old son. He disputed Trump's claims that many of the migrants are criminals.
"He is trying to find an excuse in us," Rodriguez said. "We are not aggressive. Aggressive are those who shoot up a theater and kill dozens. Not us."
Many of the migrants said they joined the caravan at the last moment, having seen a message on social media or a local news story in Honduras that inspired them to leave behind a homeland where they had given up on having a future.
On a road full of migrants carrying blue-and-white Honduran flags, the rainbow flag that Chantal Alejo and her friend Stefani Rodriguez carry stands out.
Alejo is from Honduras, and Rodriguez is from El Salvador. Both are 27 and identify as transgender, making them part of a community that faces high rates of violence and persecution in many Latin American countries.
Alejo said a posting on Facebook made her immediately pack a bag.
"There's a lot of persecution and no work," she said of her country. She and Rodriguez are hopeful they can make it to Dallas, where they have read about trans women like themselves receiving hormone treatments.
Many migrants in the caravan learned everything they know about the United States through movies and TV shows. But not Bryan Colindres.
Colindres was 6 years old when he and his mother moved from Honduras to the United States after his father's murder. Colindres said he was never able to gain citizenship, but grew up more American than Honduran.
Nearly 20 years later, Colindres' American life was interrupted by an immigration raid on the construction site where he worked. When he was deported, he left behind his wife and a 3-year-old daughter who is a US citizen.
As soon as he arrived in Honduras, Colindres headed back north, eager to reunite with his daughter.
"She's the one who needs me the most, and I don't want her to go without me," he said. "I know what it's like to not have a dad."
Colindres joined the group in Guatemala and, when Mexican police blocked the bridge that connects the two countries, he and other migrants paid about $1.25 to be taken across the Suchiate River by raft.
He has since left. Colindres took a bus to Guadalajara, where his perfect English helped him find a job at a call center providing customer service to the country he considered home.
Colindres said he hopes to earn enough money to eventually rejoin his family in the US.
Resting on a shady spot on the road to Arriaga, Mexico, Iris and her group hoped that a car would stop and give them a ride.
Iris' younger brother, Freddy, appeared to be fast asleep in the sweltering heat, using his backpack for a pillow. Her nieces and nephews played with dirty stuffed animals by the side of the road.
"The journey has been hot, and walking under the sun is the toughest thing," said Iris, who did not want to give her last name.
The 21-year-old said she was confident they would be OK if they made it to New Jersey.
"I will do whatever comes up. I will take the first job that's available," she said.
When asked whether she knew how many miles they still have to travel, Iris gave a weary sigh.
"Muchos (many)."