(CPR News/Nathan Heffel) An RTD commuter rail car enters DIA's transit center under its own power. The East Rail Line connecting DIA to downtown Denver is scheduled to open sometime in mid-2016.

﻿RTD’s commuter rail line to Denver International Airport marked an important milestone Friday when two commuter rail cars entered the station at the airport under their own electric power.

The test marks one of the final stages before the East Rail Line opens to the public in mid 2016.

During prior trips, the cars were pulled by another test engine. RTD’s Kevin Flynn said the cars arrival at the transit terminal mark a game changing moment not just for the line, but the agency itself.

“Today is the start of testing. But what you have is a line that we believe people from all over the metro area will likely use, as opposed to the rest of the system that serves individual corridors,” Flynn said.