An RCMP officer takes a last drag of his cigarette. There's word someone is coming.

Standing on a muddy mound on the Canadian stretch of a rural road that's become a freeway for people seeking refuge in Canada, the officer and two of his colleagues adjust their positions as a cab drives into view.

Three men step out.

"We have issues over here and we want a safe place to live," the apparent leader of the group mumbles to a CBC crew on the American side.

After waving aside the stern warnings from the Mounties that they'll be arrested with simple "yeah, yeah," the three men leap over a ditch, landing in Canada.

NY-Quebec border

RCMP greet three men illegally entering Quebec from Roxham Road in upstate New York on Thursday. (Catharine Tunney/CBC)

It's a leap of faith a growing number of asylum seekers are making to get around the Safe Third Country Agreement, which requires refugees make a claim in the first country they land in. People who have already made a claim in the U.S. can't then shop their claim to Canada, and vice versa.

But that rule, part of a Canada-U.S. border pact created after the Sept. 11 attacks in the United States, is limited to official land border crossings and airports.

This week, CBC Radio's The House travelled on the road to understand how the Canada-U.S. border agreement is dominating the lives of people who want to flee the United States, those guarding the border and those living near it.

Welcome to Roxham Road, fast becoming one of the most famous rural roads in America.

RAW: Asylum seekers crossing the border illegally3:55

Life on the U.S. side

There are barely any markings announcing the Plattsburgh, N.Y. bus station. It's a gas station with an A&W, a Dunkin' Donuts and a fridge stocked with beer.

A bus driver calls out that the Montreal-bound bus is preparing to leave.

He says he's noticed an increase in the number of passengers seeking to make a refugee claim.

"It's happening more often... maybe in the last few months, they've been coming more often," says the Trailways driver, who doesn't want to give his name.

It's here at the bus station where some asylum seekers sometimes hop off to grab a cab to Roxham Road, for a hefty price.

Janet McFetridge lives near Roxham Road in Champlain, N.Y., and says since President Donald Trump's election victory a few months ago, there's been an obvious traffic increase in the area.

Cab Roxham

A cab driver drops would-be refugee claimants off at the Canada-U.S. border. Plattsburgh police say they're hearing some drivers are charging up to $500 for the ride. (Catharine Tunney/CBC)

"I've seen many, many cabs go by and you do not normally see a single cab driver in Champlain. There's no reason to, people aren't normally taking cabs up north," she said.

Plattsburgh Police Lt. Scott Beebie is aware of the alleged price gouging along the route.

"I've heard as much as $500 depending (a ride) on how many people are in the cab. There's nothing the city of Plattsburgh can do," he said. "It's excessive."

U.S. Border Patrol agents and state troopers have a presence on the U.S. end of Roxham Road, but they are also limited in what they can do to deter people from entering Canada.

Swanton Sector Agent Michael Estrella says unless they catch someone who is illegally staying in the United States, no laws are being broken by leaving the country.

"We do explain to them that they must conduct a legal crossing and that has to be done at a port of entry and that they are in violation of Canadian law," he said

'I think a general unease in the direction of our immigration policy.' - Plattsburgh, N.Y. Mayor Colin Read, on the reasons for the border crossings

Frustrated by inaction, McFetridge has helped start a group trying to insert themselves into this underground cycle, offering clothes, legal assistance and money to those wishing to leave.

Plattsburgh, part of a lone wedge of northern New York state that voted Democrat in last presidential election, is not officially a Sanctuary City, but its mayor, who just six years ago became a U.S. citizen after moving from Canada, sees its role as unofficial babysitter until the asylum seekers move north.

The reason to migrate north is obvious to Mayor Colin Read.

"I think a general unease in the direction of our immigration policy.

"Many of the people coming through here actually still are legal residents or legal visitors to the country, but they're just seeing a lot of uncertainty and of course Canada has a very different immigration policy. Canada invites immigrants," he says.

Trump Congress Border Wall

A Donald Trump supporter flexes his muscles with the words "Build The Wall" written on them as Trump speaks at a rally in Plattsburgh, N.Y. during last year's election campaign. The city is the last bus stop before the Canadian border. (The Associated Press)

On the Quebec side

Their passports are different, but McFetridge and Susan Heller could be considered neighbours.

If you get past the quacking ducks guarding her front door, the smell of fresh bread greets visitors into Heller's 200-year-old farmhouse on Quebec's Roxham Road.

She's so close to the border she once illegally crossed the border just to chase down her runaway horse.

Asylum seekers used to wander past her home looking for a glass of water, but that's changed now that four RCMP vehicles are permanently parked near the border ditch, watching 24 hours a day.

"They'd roar off from zero and everything, ringing and banging all night. And I thought, 'these people want to come over. Why are they rushing to get them when they wish to be caught?'" she said.

"I went through the war. You know about evacuees? We had them in our house during the Second World War. I think it's an amazing thing and I think it's excellent that Canada says yes."

The journey to Montreal

The consequences of the Safe Third Country agreement are perhaps most acutely felt by people like Mamadou, who was found collapsed in the woods by officials earlier this month after making an illegal crossing.

He didn't want his last name used, fearing for his safety.

Roxham Road

Susan Heller talks to CBC Radio's The House at her farmhouse on Roxham Road, where these days the RCMP have a constant presence. (Catharine Tunney/CBC)

The 45-year-old Ivory Coast man had fumbled in the woods for hours in what he described as -15 C weather trying to find Canada.

"The police rescued my life," he explained from near the Montreal YMCA where he's staying.

Weeks later, he can only manage to shove his still-swollen feet into sandals.

More than the continuing pain, there's another thing gnawing at him from that day: hours earlier he had tried to make a refugee claim at an official border crossing and was denied.

And because of that, he likely risked his life for nothing.

'They're not going to be less desperate or more desperate if the (Safe Third Country) agreement is cancelled or suspended' - Lawyer Éric Taillefer

His lawyer, Éric Taillefer, says if Mamadou had started on the illegal route first, his chances of being allowed to stay in Canada would be around 60 per cent.

But because he first made a claim at an official border point, his chances have dropped to three per cent.

"When you see cases like Mamadou, where basically they put their lives at risk because of the agreement, there is a basis for Charter challenge. The only thing is that finding the perfect case to bring up is going to be a tough one," Taillefer said.

While activists and lawyers search for that perfect case, Taillefer is certain people like the three men who crossed on Thursday and Mamadou will continue to put their lives up in the air for a chance to live in Canada.

"They're doing it because they are desperate. They're not going to be less desperate or more desperate if the (Safe Third Country) agreement is cancelled or suspended."

Cda US Border Refugees 20170217

Family members from Somalia are helped into Canada by RCMP officers along the U.S.-Canada border near Hemmingford, Que. Photos like this are garnering international attention for the RCMP. (Paul Chiasson/THE CANADIAN PRESS)