It’s the lifeline of Cape Cod. To many of us, it ends at the bridges. But Route 6 is actually by most accounts the second-longest highway in America, running from Provincetown to California.

It’s the lifeline of Cape Cod.

To many of us, it ends at the bridges. But Route 6, officially at 3,249 miles, is actually the second-longest highway in America, running from Provincetown to California. The longest is 3,365-mile Route 20, which runs Boston to Yellowstone National Park in Wyoming.

Also known as the Grand Old Highway, a nod to the Grand Army of the Republic Highway, the roadway is falling out of use and out of the consciousness of the American public in favor of bigger interstates and air travel. However, there is a growing push to change that.

The U.S. Route 6 Tourist Association is a not-for-profit organization focused on economic development and cultural preservation of the 600-plus communities along Route 6.

“A lot of people who live along Route 6 don’t know where it goes,” says Russell Lombard, president and CEO of the organization dedicated to telling the story of Route 6.

The U.S. Route 6 Tourist Association started as a school project for Lombard’s teenage neighbors.

High school students Jennifer Harrison, Hilary Oppelaar and Karla Hartle, who live nearby, needed a subject for a Web site design project and Lombard suggested they do the history of Route 6.

Lombard, who lives in Port Orchard, Wash., grew up in Southern California and would frequently travel with his parents to visit relatives in Nebraska and Illinois, using Route 6. Lombard’s love of Route 6 soon became an obsession for his teenage neighbors.

“We really knew we had them hooked when they told their friends they couldn’t go to the mall on the weekends,” says Lombard, who assisted the students with his wife, Mary.

That was 2001. Six years later the high school project is a not-for-profit organization linking 600 communities in 14 states across the continental United States.

Since working with about 600 towns would prove a formidable task, the association is working to create 14 state chapters.

“Each state has their own special interests,” says Lombard.

California, Nebraska, Pennsylvania and Connecticut have working chapters.

The Route 6 association is speeding along, but is starting to hit a few potholes here in Massachusetts.

The organization, with little to no budget, provides signs at cost, which range from around $95 to more than $200, depending on the size.

Communities that are members of the association receive a $50 discount. Of course, the group wants a sign in Provincetown, which is either the beginning or the end of the road, depending on where you are headed.

Provincetown has an informal agreement with Bishop, Calif., to mark the termination points of Route 6.

But when the highway was built in the 1950s, Route 6 went all the way to Long Beach, until a stretch of the road in California was decommissioned in 1965. So while technically Route 6 now ends in Bishop, historically it went to Long Beach.

Provincetown’s administrative tourism director Bill Schneider says he would want to make sure that Bishop is OK with the arrangement before anything changed about the sign on Route 6 near Herring Cove Beach.

Lombard says he hasn’t heard anything from anyone in Bishop. And Los Angeles County just requested a big order of signs to mark the historic road to Long Beach.

But there is a bigger problem.

Despite recent changes, Route 6 is still under state control when it comes to signage. Signs along Massachusetts’ highways must be constructed following state safety codes and it must fit other regulations, which could drive costs up to $8,000.

“You add those two components together and already you have a bureaucratic nightmare,” says Schneider, who nonetheless is speaking to the town’s department of public works and Town Clerk Doug Johnstone to see what can be done.

This is a stumbling block unfamiliar to the U.S Route 6 Tourist Association.

The response nationwide has been tremendous, since many spots on Route 6 in the Midwest are towns that are dying as the economy crumbles, especially in Nebraska where the governor recognized the group’s efforts.

“Every town we’ve been to before, we just show it to the mayor and that’s it, they say, ‘Let’s do it,’” says Lombard. “We haven’t had any problems.”

Learn more

The U.S. Route 6 Tourist Association Web site is route6tour.com.

The organization, with little to no budget, provides signs to communities at a cost from $95 to more than $200, but Massachusetts’ sign regulations could drive up those costs to as much as $8,000.