Interstate 70 starts its eastward course near Old Cove Fort in Utah, crosses the mighty Rockies by tunneling under Colorado's 11,990-foot-high Loveland Pass, traverses the Great Plains and meanders through the rolling hills of Pennsylvania before dipping into Maryland.
And there, after a heroic journey of 2,153 miles, it comes to an inglorious end: a park-and-ride lot just inside the Baltimore Beltway.
That could change under a plan being considered by two state agencies to lop off, or severely truncate, I-70's awkward two-mile vestige inside the Beltway.
The Maryland Transit Administration is looking covetously at the interstate right-of-way as a potential path for the east-west Red Line, while the State Highway Administration sees the possibility of reducing pollution from its paved surfaces. If the idea passes muster, I-70 would in effect end at Interstate 695, though a ramp would still extend to a parallel road that just happens to be called Parallel Road.
The plan is still in the conceptual stage, said Henry M. Kay, the MTA's executive director of transit development, but the agency has outlined it to groups such as the Red Line Citizens Advisory Council.
"It looks like a win-win to us, but we have to work these things through," Kay said. The Red Line is a proposed 14-mile light rail line that would run from Woodlawn to Johns Hopkins Bayview Medical Center through downtown Baltimore. One reason he's discussing the proposal openly, he said, is to encourage feedback from the public.
The I-70 proposal would use a relatively narrow strip of the existing roadway for the transit line as it heads eastward from Security Square Mall. A Red Line station and a surface parking lot would be built in the loop of an existing interchange at Ingleside Avenue. The final mile of the eastern end of I-70 would be snipped off. Gone would be the existing park-and-ride lot and the loop that runs around it.
One reason highway engineers aren't dismissing the idea out of hand is that the interstate carries relatively little traffic inside the Beltway.
Decades ago, plans called for I-70 to continue eastward through Leakin Park before connecting with Interstate 95 in Southwest Baltimore. But fierce community opposition in West Baltimore scuttled that plan. Inside the Beltway, I-70 became a glorified feeder route to the Social Security Administration campus in Woodlawn.
Dan McNichol, author of "The Roads That Built America: The Incredible History of the U.S. Interstate System," said Baltimore is one of several cities where highway officials built the "easy miles" of an interstate only to be blocked as they tried to continue through urban neighborhoods. But McNichol was unaware of any other highway that ends quite the way I-70 does.
"The parking lot, I think, is unique to Baltimore," he said. In some places, miles of the Interstate Highway System have been decommissioned, but that is fairly unusual.
One reason Maryland's highway agency is considering such a step is the possible benefit of tearing out acres of pavement. Under pressure from the U.S. Environmental Protection Agency to reduce runoff from its roads and protect the Chesapeake Bay, highway officials are considering whether to let parts of the roadway return to a more natural state. That could help the agency reach mandated goals while also aiding the MTA.
"We think it's an opportunity for both of us to derive some benefit from it," said Kirk McClelland, director of the agency's Office of Highway Development. "We have the opportunity to remove pavement and reconfigure traffic and help us with our water quality requirements."
The highway agency has also had concerns over the years about the use of that stretch of I-70 as a late-night drag strip. That use turned deadly on June 21, 2009, when a man who was later found to have been legally drunk crashed his car into two pedestrians who may have been spectators at such a race. Jonathan Henderson, 20, and his girlfriend, Mary-Kathryn Abernathy, 21, died.
McClelland said barriers erected in the aftermath of that crash have curbed drag-racing. But the Red Line proposal, he said, "would be a more permanent solution because we'll actually take the pavement away."
Still, he emphasized that the highway agency hasn't taken a position on the proposal.
In designing and building the Red Line, the I-70 right-of-way offers significant advantages, said Ken Goon, a consulting engineer with RK&K who has been working on the light rail line for the MTA.
Goon said that using the roadway would spare the MTA the cost of building a bridge for the Red Line over Woodlawn Drive. It would also give the line a straighter path into the planned tunnel under Cooks Lane, allowing trains to run at faster speeds and to face fewer operating difficulties than on a more curved path.
The plan could also eliminate the need to cut down trees to build the transit line along the north side of the existing interstate, Goon said. Instead, it would run on top of the existing westbound lanes — farther from an apartment complex on Ingleside Avenue. Traffic from I-70 would be shifted to a lower-speed road.
"It would be less highway noise and highway intrusion into the neighborhoods," Kay said.
Any plan to take miles out of the interstate system would have to be reviewed by the Federal Highway Administration. Kay said the MTA is also working with the Social Security Administration and the federal General Services Administration to address issues of employee access or possible land transfers along the northern edge of I-70, where the U.S. government owns much of the acreage.
The proposal requires study to determine whether it would maintain traffic flow in the Woodlawn area, Kay said. But he added that the early indications are positive.
Sandy Conner, a member of the Red Line advisory committee and a resident of the Woodlawn area, said she had some concerns about whether the change would impede traffic but has since been reassured. Now she thinks it could help beautify the "bleak" area around the park-and-ride lot without causing significant problems.
Conner said it might take neighbors some time to adjust.
"Like any change, there will be some uneasiness," she said. "If they can see the ultimate benefits, I think they'll come to appreciate it."