Chicago's rails-to-trails project known as the Bloomingdale Trail remains a construction site, but the planned biking and pedestrian passageway is taking shape as crews carve out shallow valleys that will add small hills and dales along the otherwise flat route.

On a recent hard-hat tour of the construction site on the city's Northwest Side, RedEye got a chance to walk the route whose contours are a departure from the flatland that is Chicago. The 2.7-mile east-west trail runs between Armitage and North avenues, from Ridgeway Avenue east to Ashland Avenue.

When you consider the designer behind The 606—the newly dubbed name for the elevated trails and street-level parks that will hug the route—the elevation changes aren't necessarily a surprise. New York-based Michael Van Valkenburgh, a graduate of the University of Illinois at Urbana-Champaign, is also the chief designer of Maggie Daley Park, an under-construction landscape east of Millennium Park that also will feature hilly terrain constructed from an otherwise flat field. Van Valkenburgh couldn't be reached for comment.

"Chicago is extremely flat, so the elevation changes in the Bloomingdale Trail will provide something many of us don't see every day," said Beth White, Chicago regional director for the Trust for Public Land, the private foundation spearheading the $95 million project.

The trail will be wheelchair accessible and White said the slight elevation changes should be navigable for anyone.

EXTRA: How to transform a defunct rail line into a trail park

"The entire trail and access ramps were designed to meet all ADA [Americans with Disabilities Act] accessibility requirements so that everyone can enjoy it," she said.

Like New York City is doing with the High Line, Chicago is one of a growing number of U.S. cities converting defunct rail lines into elevated parks with the help of big-name landscape architects.

Construction has been slower than expected, thanks in part to an unusually cold winter that froze the ground anywhere from four to 10 feet deep in many places. Plans for the next phases of construction were announced last month, along with a new date for The 606's completion: June 2015.

Other planned features of The 606 are still hard to imagine, such as a hill and observatory at the far western end of the trail, and a park at the foot of the trail. And while the trail itself is uneven soil and rubble now, it eventually will become a concrete road, 10 feet in width, bordered by two feet of rubber walkway on either side. The goal is to give runners, cyclists and casual users of the trail alike room to navigate around each other, planners said.

For those who want to stop and appreciate the views from above some of the West Side's expansive boulevards, there will be poured concrete seating along the railings where the bridges cross over Humboldt Boulevard and other roads, planners say.

"It's going to be pretty unique; you have this ribbon of green cutting through the community, and sort of this earthen structure that's bound to the earth, and you'll have these parks that are like gateways," White said. "It will be a lush landscape. Lots of trees, places you can sit and be contemplative."

So far, the project's starkest visual change has been the removal of the Ashland Avenue Bridge, which was lifted at the end of March and re-installed over Western Avenue in April. White said developers also plan to announce another bridge-moving in the coming months, this time at the intersection of Milwaukee and Leavitt avenues. The bridge there will be lifted, she said, so a new support system can be installed underneath.

Once completed, the Bloomingdale Trail could draw many tourists to Logan Square and Humboldt Park for the first time, but some residents around Bloomingdale Avenue already have a long history of climbing up to the tracks—technically trespassing—to get a rare, free view of the city from above.

"It was really the most intrepid trespassers who went up there, and there were definitely some illicit things that went on up there, but for the most part, it was people looking for a place to get away," said Ben Helphand, board president of the nonprofit Friends of the Bloomingdale Trail, which helped plan its redevelopment.

EXTRA: The 411 on naming The 606

Helphand said the rail's elevation and secludedness has drawn people up to the site for years, for a gamut of activities, from jogging to drug use to, in his case, taking engagement photos.

"The trail is only 16 or 17 feet tall, but Chicago's so flat, the views are wonderful," he said. "If it was just a railroad bed, it wouldn't have captured people's imaginations like this."

Realtors have been eyeing the project for its potential to attract home buyers.

Then there are the folks living in the neighborhood like Jonathan Surratt, 40, of Logan Square, who owns a townhome that overlooks the trail near Rockwell Avenue. He said he is looking forward to the changes the trail likely will bring to the neighborhood, including more vibrant street life and higher property values. But the project has caused a few headaches, too, including the elimination of parking spots near his property.

"Right now, people going from East to West are not going down my street, they're going on North [Avenue] or Armitage [Avenue]," he said. "If anything, I think it will make the street more active, and noise could be an issue. Our bedroom windows are right at the level of the trail. If teenage kids are running back and forth screaming and yelling, we can hear it."