Mount Airy, MD: The "Old B&O Main Line"

(Satellite, note there is a short tunnel under Main Street and Ridge Road)

Mark Hinsdale posted four photos with the comment:

"Old Main Line"
The original Baltimore & Ohio route from Baltimore is appropriately known today as the "Old Main Line. It headed away from the city and toward the west by following the Patapsco River, through the hilly terrain past Relay, Ellicott City, and Sykesville. At Mount Airy, the line crested Parr's Ridge and began the slow descent to the Potomac River valley at Point of Rocks. The climb to Mt Airy was significant, in both directions, but especially against the slow moving eastbound coal and grain trains bound for the Port of Baltimore that typically traverse the line, in order to keep them clear of the newer, busier, and more favorably graded line through Washington DC. A tunnel under the top of the ridge at Mt. Airy marks the summit. Here, on a cold winter day, eastbound coal is working its way toward and through Mt. Airy, and also meeting a westbound at the siding just west of the tunnel, known as Plane. January, 1984 photos by Mark Hinsdale

1

2

3
Pete Darmody Great shot includes the unique B&O color position light signals (CPLs) that are now mostly gone

4