After Keystone 656 rolled east through Gap, I had but a short wait for its westward counterpart, train 651, destined for Harrisburg and led by ACS-64 620.
In the short interval between trains, I thought about all the Pennsylvania Railroad electrics that worked through this same curve more than a half-century ago.
In 1963, my father made photos of GG1s and E44s working trains near the Irishtown Road crossing in Bird-in-Hand. Someday, I’ll recreate those angles with modern trains.
What is common today will someday seem novel.
What was once working the Main Line may someday serve as a display at the Railroad Museum of Pennsylvania. I wonder, did I catch old Amtrak 915 at Gap? I may have.

Today, Tracking the Light ponders the numbers and the passage of time.