LYNCHBURG, Va. -

A unique method for digging tunnels is being used on a Lynchburg road project.

Liberty University is building two tunnels to connect its campus with Wards Road.

Because construction is happening underneath a set of busy railroad tracks, contractors are trying something that's never been done in the United States.

They're pulling concrete boxes under the railroad, using hydraulics and heavy cables.  Each box weighs more than 4-million pounds.

Liberty University's chancellor Jerry Falwell, Jr. flipped the switch Monday morning to start pulling the boxes under the railroad.

"This method has been used widely in Europe, but this is the first time here," Falwell explained.  "It took us seven years to get it approved by the railroad."

It will take about a week for the boxes to be pulled under the railroad.  The new tunnels are scheduled to open in January.