(WBIR - Blount County) High along the ridge-tops in Blount County between Walland and Wears Valley, crews continue bridging a longtime gap in the Foothills Parkway known as the "missing link."

Construction on the parkway with spectacular views of the Great Smoky Mountains National Park began in the 1960s. However, funding problems and environmental concerns repeatedly interrupted work at the 10-mile section of the road between Wears Valley and Walland.

Lane Construction, the contractor working on the project, is now simultaneously building five remaining bridges needed to complete a final treacherous mile of the route that spans a series of peaks and valleys. The "missing link" at this point is actually five small missing links.

"I don't think there's anybody who does this on a regular basis. It's unique in my career," said Tom Meador, project manager with Lane Construction. "I've spent the last two years up here. We're doing what's called top-down construction. This is probably one of the most intense projects you can work on with the steep terrain."

Meador said one of the greatest challenges as they continue plugging away at the final five bridges is planning and coordinating crews with large equipment to navigate a route that provides limited access.

"Obviously we don't want to disturb the environment as much as possible. So a lot of the areas we have are one-lane road," said Meador. "When you have this much large equipment moving in and out on a one-lane road, it takes some planning."

One lane of progress is a big improvement considering the project seemed destined for a dead end just a few years ago. Federal stimulus money put the project back on track. Last June, the Park celebrated the completion of one of the most complex bridges along the route. "Bridge Two" spanned more than 800 feet and could only be built from one side.

LINK: June 25, 2013 - Massive bridge completed along "missing link"

Now the task facing crews is completing bridges three through seven.

"This is a project that has been a long time coming and it is very interesting construction," said Charles Sellars, chief of facility management for the Great Smoky Mountains National Park. "It is a real challenge, in particular this section of the parkway because of the number of bridges and the cuts that are required."

The parkway does not cut into the mountainside the same way many highways are constructed along hillsides. Rather, the road is winding supported deck with one side of the road hugging the curvature the mountainside while the opposite lane extends out among the clouds.

"The design of this roadway, we wanted to give the visitor the experience of basically driving along at tree-top level. It is meant to give people as sensation where you are part of the environment," said Sellars.

Once the five bridges are complete, there are nine miles of existing road that is crumbling along the closed route. The road will have to be resurfaced and parking pullouts along overlooks will be built.

When the road is finally complete, Sellars and Meador say drivers will finally see what they've been missing.

"Being able to look back into the Park and also look down into some of the communities. There's no doubt we're providing views that would not otherwise be available," said Sellars.

"Just the spectacular views they're going to have once we're done up here. It is amazing. It is something I've been able to enjoy working up here for the last two years and I cannot wait to share it with everyone," said Meador.

Sellars said it is difficult to predict an exact completion date at this time. Last year the government was hopeful an aggressive construction schedule could allow the "missing link" of the Foothills Parkway to be complete in time for the National Park Service's 100th birthday celebration in 2016. However, Sellars said the current likelihood is the project will require more time to complete, possibly wrapping up sometime in 2017.