I rode the Rockville Limited this past weekend, which started at Harrisburg PA, went to Phila. via Amtrak, then onto the Northeast Corridor down to Perryville MD. Returning to Harrisburg via the Port Road, Shocks Mills Bridge and the Enola branch. Then across the Rockville bridge (100yr. anniversary of the bridge was the reason for the trip) & back to Harrisburg station. Along the way, I was thrilled to see several PC signs STILL in service! I spotted green signs at LEAMAN on the HBG-Phila line (pretty sure it was PC-it went by REAL quick!), Landlith (on the NE Corridor near Wilmington), and DAVIS tower, also on the NE Corridor. I'll bet there were more, but those were the ones I saw. In particular, to see DAVIS tower, with the PC sign still on it & the tower still in use (I think?) was quite a thrill!