For most residents of the U.S. and Canada, crossing the border between the two countries has always been quick and easy: Show some identification, answer a question or two and enter another country.
But that may soon be changing.
New federal regulations going into effect over the next three years may require all people crossing the more-than-3,000-mile-wide border to show a passport (search).
Critics say this requirement will limit travel and hurt business. Some are concerned that tighter border control (search) may infringe on personal rights.
But supporters say the move will make it harder for terrorists and drug pushers to enter the United States.
Click in the video box at the top of this page to watch a report by FOX News' Rick Leventhal.
"We want to make sure we secure the border — we're both committed to that," said Frank McKenna (search), the Canadian ambassador to the United States. "But we also want to make sure our citizens still enjoy some of the freedoms that we're fighting so hard for."
Currently, residents of both countries have no problem crossing the bridge over the St. Croix River (search) between Calais, Maine and St. Stephen, New Brunswick, several times a day.
The process of going through customs is usually a breeze — people cross with a wave and a smile if they're recognized, and present only a driver's license if a border agent asks for ID.
Cindy Calhoun lives in St. Stephen, but does a lot of shopping just across the border in Calais.
"It's not like there's a border that separates the two, because both are so close, and both get along so well," Calhoun said.
Only 20 percent of Americans own passports, and residents of Calais say the percentage is actually lower in their border city, where the average income is just $24,000 a year.
Passports cost $97 to get for the first time, and some local families say at that price, they won't be able to cross the bridge any more.
"For just our family to have a get-together at our cottage would be $1,500, because everyone would have to have a passport to cross the bridge," said U.S. resident Lorraine Mitchell."It's just crazy. I mean, I go across the bridge three times a day."