Montgomery County in the US State of Maryland will build a double-track rail line as part of the Washington Metro transportation system's 25km Purple Line.
The rail line will run between downtown Bethesda and Langley Park, Montgomery's section of a transit link.
Montgomery's Purple Line plan includes more access points to the Georgetown Branch trail, according to washingtonpost.com.
The Maryland Transit Administration is handling the Purple Line's construction, estimated to cost $1.68bn.
