BETHESDA, Md. —  Medical staffers and wounded warriors in Bethesda will have a better — and safer — way to get from the Medical Center Metro station to the Walter Reed National Military Medical Center in a few years.

A new pedestrian underpass, built with $110 million in federal funding, will make the crossing easier and less perilous. The project is slated to begin in mid-2017 and is expected to be completed by late 2020.

The number of pedestrians from the Metro station trying to make it across busy Maryland Route 355/Rockville Pike has more than doubled after the center moved to Bethesda as part of the federal base relocation program.

The underpass aims to provide safe passage for bus and carpool passengers arriving at the transit center and pedestrians from nearby areas, who account for almost 20 percent of street crossings.

But the construction won’t alleviate traffic anytime soon, since excavation for the tunnel will mean lane closures.

The money will also pay for the construction of high-speed elevators at each end of the pedestrian access route: at the Medical Center Metro station mezzanine on the west side of Route 355 and at Walter Reed’s main entrance on the east side.