Along the Arizona-Mexico border (CNN) Marisela Ramirez's hands tremble as she rubs them together to control the shaking. The dirt under her fingernails hints at the hardscrabble journey she's endured since leaving her home in southern Mexico weeks ago.

Ramirez is in Nogales on the Mexican side of the border with the US -- sitting in a shelter eating breakfast -- no more than 100 yards from an Arizona town bearing the same name. But for this 18-year-old from the state of Oaxaca, that line in the desert might as well be on the other side of the world.

Three weeks ago, Border Patrol agents arrested Ramirez and her brother, along with a small group of migrants, as they tried to cross illegally into the Arizona.

"The experience left me traumatized. I have never tried crossing before," Ramirez told CNN. "I was scared."

She was quickly deported to Mexico, and when CNN spoke with her she was waiting for her brother to be released so they could figure out what do next.

Ramirez says poverty drove her to make this journey north. She wants to find work in America to support her elderly parents.

"We want to find a dignified job," Ramirez said. "We didn't even have enough money for me to finish going to school."

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A dangerous journey

Crossing the border illegally into the United States is a danger-filled journey. Immigrant rights activists have long warned that the human smuggling routes, often controlled by ruthless "coyotes" (smugglers), are potentially deadly threats for female migrants.

According to the US Border Patrol, of the almost 409,000 migrants apprehended in 2016 along the southern border, 101,000 were women.

Statistics for assaults of female migrants are difficult to collect because many of these crimes often go unreported. In 2010, Amnesty International reported that as many 60% of migrant women and girls traveling through Central America and Mexico were sexually assaulted.

In a report titled, " Invisible Victims: Migrants on the Move in Mexico ," researchers wrote "the threat of sexual violence is often used a means of terrorizing women." And the report said, "Many criminal gangs appear to use sexual violence as part of the 'price' demanded of migrants."

Women and migrants are urged to travel in groups, not to carry identification or phone numbers of relatives in their wallets or backpacks.

It was another migrant who was deported with Ramirez who told her about the Kino Border Initiative , the shelter where she's eating breakfast, in this Mexican border town.

A team of volunteers cooks meals for the migrants. The shelter offers free phone calls to relatives, basic medical checks and clothing and shoes.

The Kino Border Initiative opened in 2009 and is run by Jesuit priests and several humanitarian organizations. Father Sean Carroll greets the migrants many mornings. He says part of his mission is to "humanize" the people he sees every day.

Father Carroll has sensed an increasing fear in the United States of the threat perceived to be pouring in through the country's southern border. He worries that fear has made many Americans lose sympathy for migrants who are risking their lives in search of a better life.

"People are concerned for their safety. They are concerned that there is a real lack of order," Father Carroll said. "We need security. We need safety. But I don't believe border security and respect for human dignity are mutually exclusive. We can do both."

Father Carroll and many immigrant rights activists insist comprehensive immigration reform is the best way to ensure border security.

"So the more we address the root causes of this issue, I think we are going to have fewer migrants crossing. That would mean we would need fewer resources to secure the border and those resources can be really focused on people who want to do harm," Carroll said.

Photos: Views from the border The US-Mexico border spans 1,933 miles. It runs from the Pacific Ocean to the Gulf of Mexico, across California, Arizona, New Mexico and Texas. President Trump's pledge to build a wall along the border was a key part of his campaign. He said this month that early construction of the wall would be funded with US tax dollars in order to get started quickly, and promised that Mexico "will reimburse us." Click through this gallery to see scenes from the border and perspectives from those who live and work near it. Hide Caption 1 of 20 Photos: Views from the border Pamela Taylor, 88, has lived in Brownsville, Texas, since 1947. Taylor says she has had people from "all over the world" arrive on her property, and she says she has even found them in her living room. Every night, she fills a cooler in front of her house with bottles of water for migrants who made the journey, Border Patrol officers, or anybody else who finds themselves near the front steps of her house. Hide Caption 2 of 20 Photos: Views from the border Taylor put this sign up down the road from her house during the 2016 presidential election. She says that the fence the US government put up near her property in 2007 doesn't work. "I would like for Mr. Trump, I would even feed him, if he will come down here and talk to the people," Taylor told CNN. "He is doing exactly what the government did to us in the beginning. He's not asking how it's going to affect the people that live here." Hide Caption 3 of 20 Photos: Views from the border The Rio Grande forms a border between Texas and Mexico. Much of the river straddles remote desert and farmland, such as this stretch in Progreso Lakes, Texas. Hide Caption 4 of 20 Photos: Views from the border On October, 26, 2006, President George W. Bush signed the Secure Fence Act, and said, "This bill I'm about to sign is an important step in our nation's efforts to secure our border and reform our immigration system." More than 1,250 miles of the border are in Texas, but the state only has about 100 miles of man-made borders. This fence line in Progreso Lakes, Texas, comes to an end, and leaves miles of border land open. Hide Caption 5 of 20 Photos: Views from the border Greg Henington, owner of Far Flung Outdoor Center in Terlingua, Texas, says he doesn't believe a wall is necessary. "The wall is not going to make a difference one way or another. It's just going to cost a ton of money and look dumb." Hide Caption 6 of 20 Photos: Views from the border In 1935, the federal government passed legislation that would enable the state of Texas to acquire the land that would become Big Bend National Park. The park, known for its remote beauty, shares the border with Mexico for 118 miles and is separated by the Rio Grande. Hide Caption 7 of 20 Photos: Views from the border Lilia Falcon owns Jose Falcon's restaurant in Boquillas del Carmen, Mexico, across the Rio Grande from Big Bend National Park in Texas. The border crossing closed after September 11, 2001, and reopened in April 2013. "This town just went dead," Falcon told CNN. "We are very happy that the border is reopened again. We feel very safe here, even tourists that come over here, the word is spreading out more that its very safe to come here." Hide Caption 8 of 20 Photos: Views from the border Many Texas residents in the Big Bend National Park region believe that the various miles of remote canyons and rivers already act as an "effective barrier" with Mexico. Hide Caption 9 of 20 Photos: Views from the border Robert Cameron, owner of Texas Border Tours in Progreso Lakes, Texas, is in favor of President Trump's proposed wall, but he knows it will be complicated to build through parts with rough terrain. "I want to see a wall," Cameron told CNN. "Not a fence. I want to see a wall. I want to see something that you can't see through, that you can't climb through." Hide Caption 10 of 20 Photos: Views from the border The scenic mountains, canyons and desert that make up the Big Bend region on the west Texas-Mexico border span an elevation of less than 1,800 feet near the Rio Grande to almost 8,000 feet in the Chisos Mountains. Hide Caption 11 of 20 Photos: Views from the border Michael Ryan has worked as a ranger at Big Bend National Park since 1999, and 10 years as a river guide in the region previously. "It's not just one border, it changes depending on where you are," he told CNN. Hide Caption 12 of 20 Photos: Views from the border The Boquillas Crossing, a one-of-a kind port of entry where you can take a small ferry boat across the Rio Grande and into the tiny Mexican village, reopened on April 10, 2013, following federal closure for more than a decade after the September 11, 2001, attacks. Hide Caption 13 of 20 Photos: Views from the border Marcos Paredes has lived near Terlingua, Texas -- a former "ghost town" -- for much of his life. He spent years as a law enforcement officer responsible for patrolling the Rio Grande. "To come up with a one-sized fits all solution for illegal immigration is crazy," Paredes told CNN. "Because the border is so different along its entire links." Hide Caption 14 of 20 Photos: Views from the border Alicia Bon Martin, born in Nogales, Mexico, and her husband, Chris Martin, work and live on both sides of the Arizona-Mexico border. They own organic farms in Mexico, a produce distributorship, and the restaurant La Roca, a Nogales, Sonora, institution started by Alicia's uncle and celebrating its 45th year anniversary this year. "We are lucky because we have the good things of both sides," Alicia told CNN. "I see this border as a much calmer than anybody portrays it to be." Hide Caption 15 of 20 Photos: Views from the border Tim Foley founded The Arizona Border Recon in 2011, a nongovernment organization which provides intelligence to the US Customs and Border Protection. Foley has set up about a dozen cameras in the Sasabe, Arizona, desert and shares a database of smuggling activity that he says he captures with the Border Patrol. "It's a huge game of hide and seek," Foley told CNN. "A wall might help a little bit. But we have a wall here, or a fence, or whatever you want to call it. And it's not a deterrent -- it just slows them down for 10 seconds. So unless you have people watching the wall, it's not going to do anything. You need boots on the ground." Hide Caption 16 of 20 Photos: Views from the border There are about 700 miles of fence along the 1,933-mile international US-Mexico boundary. This stretch in Sasabe, Arizona, has a fence that was built in 2007. "I think a barrier, a physical barrier, is definitely necessary," Shawn Moran, vice president of The National Border Patrol Council, told CNN. "Putting up a fence, putting up a wall, has stopped the vehicle loads from coming across the border. It has been almost 100% effective in doing that." Hide Caption 17 of 20 Photos: Views from the border The westernmost part of the U.S.-Mexico border overlooks the Pacific Ocean, inside California's Border Field State Park outside San Diego, and adjacent to a public beach in Tijuana, Mexico. This area is known as Friendship Park/El Parque de la Amistad, a historic meeting place where generations from both nations have gathered to visit with family and friends "across the line." Hide Caption 18 of 20 Photos: Views from the border The Galvez tunnel was discovered by US authorities in 2009, approximately 20 yards north of the national boundary in Otay Mesa, California. The tunnel is about 6 feet high, 4 feet wide, and goes about 70 feet below Earth's surface. According to Homeland Security Investigations special agent Juan Munoz, their San Diego-based task force has discovered more than 29 of these sophisticated tunnels in the past decade. Hide Caption 19 of 20 Photos: Views from the border A US Customs and Border Protection officer patrols the fence in Otay Mesa, California. Patched holes in the fence are a common sight along this section of the border next to Tijuana, Mexico. Hide Caption 20 of 20

Securing the border

On the other side of the border, the tools for capturing migrants have grown as sophisticated as ever. In the past 10 years, border fencing and barricades have grown to cover nearly 700 miles. There is an elaborate system of cameras and underground sensors monitoring vast swaths of the borderlands.

There are roughly 20,000 Border Patrol agents working in the agency, but the National Border Patrol Council, the union representing the agents, says the force is down 1,600 agents.

The National Border Patrol Council is celebrating the election of Donald Trump. Spokesman Shawn Moran says the Border Patrol has never received public support, and employees are eager to see what happens.

"The day after the Election Day, we were slapping each other on the back and hugging," Moran told CNN.

With Trump announcing a new series of executive actions focused on immigration, Moran argues that talk of comprehensive immigration reform would inspire more migrants to race for the southern border.

"Anytime we talk about a general amnesty or immigration reform, we see these surges," Moran said. "We have a serious issue with allowing immigration reform to go forward."

Moran says before the country can have immigration reform, the border must be secured.

And, in some areas, there are private citizens taking the pursuit of border security into their own hands.

Tim Foley has set up about a dozen cameras in the Sasabe, Arizona, desert.

Tim Foley created a band of border vigilantes called Arizona Border Recon. He moved from Phoenix to the border town of Sasabe and now spends his days tracking migrants and drug smugglers. Foley says he could spend his life taking vacations and sitting on his couch but he'd prefer to spend his time patrolling the front lines.

"All the major activity takes place in the mountains," Foley told CNN. "They love the mountains because less road means less border patrol, and less border patrol means easier times."

The Southern Poverty Law Center, which says it monitors hate and extremist groups in the United States, says Foley's group is made up of "native extremists."

"I've been called everything in the book," Foley told CNN. "I've been called a domestic extremist."

Foley says he has about 250 volunteers from around the country who carry out surveillance missions in this border region south of Tucson.

The teams place hidden cameras in the areas most often used by drug smugglers. Foley downloads the videos and often shares what he calls "the intelligence" with Border Patrol agents.

Foley says he's spent $120,000 on cameras and electronic equipment to do this work. But, he argues, Border Patrol agents need to work more effectively.

"You need boots on the ground," Foley said. "When you are reactive to a problem, you are always going to be behind the solution."

Foley is unapologetic and welcomes the criticism of his tactics. He spends his days traversing the terrain, and even though he supports Trump, his faith in the "system" is minimal.

"Do you know why they call it the American Dream?" Foley asks as we drive through the desert hills near his home. "Because you have to be asleep to believe it."

But on the other side of the Arizona-Mexico border, it's that idea of the American Dream that Jesus Garcia is chasing.

He left Honduras the day before Trump was elected. Garcia says he wanted to reach the United States before Trump assumed office and feared the new President would start cracking down on immigration laws.

"I want to work and find a better life for me and my family," Garcia told CNN as he sat just feet from the border strategizing the safest way of sneaking across the border.

Garcia has spent almost two months traveling along the borderlands. He's made three attempts to cross, but he's backed out each time. A few weeks ago, he got lost in the desert in the New Mexico hills for five hours, eventually turned around and returned to Mexico.

Garcia pulls out a map that's specifically made for migrants. It shows the safest and most effective ways to cross through Mexico. It includes details of where rail lines are located and where shelters are located and the services they offer.

It's a snapshot of how this underground world operates.

"It's not easy to cross the border," Garcia told CNN. "People think it's easy, but without a smuggler it's not easy."