This three-year project involved raising vertical clearances in 28
tunnels on the line between Bellvue, Ohio and Roanoke, Virginia to
allow the operation of double-stack intermodal trains. The line was
already largely double-track and engineered to cope with large volumes
of heavy loads, but much of the route along the Kentucky-West Virginia
border runs through mountainous terrain, ducking in and out of tunnels
ranging in length between 53m and 1006m.

Until now NS double stack services between Chicago and Norfolk have
travelled either by a southern route through Knoxville, Tennessee
(2159km), or north through Harrisburg, Pennsylvania (2034km). At
1659km, the Heartland Corridor is 375km shorter than the northern
route, reducing transit times by up to two days.

NS has invested around $US 141 million in the $US 261 million
public-private partnership which has also been supported by states
along the route and the federal government.

The project included the creation of a $US 68.5 million intermodal
terminal on the site of the former Rickenbacker Air Force Base near
Columbus, which was completed in December 2007 and has capacity to
handle more than 250,000 trailers and containers per year.