Daily Archives: October 20, 2020

Rock Creek Trestle: Pointing to Georgetown

This post is sort of a mental dump from several months ago regarding a curiosity I discovered while doing research on the Rock Creek trestle for the model I’m constructing. Good photos of the trestle are very rare. Doubly so for older photos from the 1940s and earlier. The trestle was located in an area with a decent amount of vegetation and was a bit out of the way. I only have a few images of the trestle that date from the timeframe in the 1940s-1950s that I model, and they are mediocre shots at best. It was a difficult structure to photograph! But, they are like gold to me. They are all I have! They are the only visual representations of something that was very special and existed in various arrangements over time due to rebuilds, strengthening, vandalism/fire and flooding damages.

Ca. 1967. Photog unknown. Collection of W. Duvall. An arsonist’s fire gutted the trestle five years before Agnes would destroy half of it in the major flooding of Rock Creek. Note the diagonal supports on the outside of the trestle. So which side of the trestle was this photo taken from?! North or South?

Because there are no strikingly significant differences between the North and the South side of the trestle, I have always struggled to determine what I was actually looking at in the photos; North or South side? The small refuge bays that jutted out a few feet at the top were offset on each side in the same relative place, so if you stood on the ground below the trestle and snapped a photo, it would look nearly the same from either side. I had to find a way to figure out which side was which when looking at photos taken from the ground! But how?

Anyone else remember this moment from It’s a Mad Mad Mad Mad Mad World? This was me moments before figuring out how to identify the North and South side of the trestle.

First let’s take a look at the bridge sketch. This view would be standing on the south side, facing north.

Bridge Sketch, B&ORRHS. Ca 1959, shows bridge after reinforcements were added.

As I studied photos there was one thing that stood out to me. The large diagonal OUTER cross braces seemed to form an arrow that pointed toward the west. I first took a look at a few known photos that I shot of the East end of the trestle to see if there was something to this. Here is a view from the North side, facing South:

11/12/2019, North side, East end. Outer braces highlighted in blue.

And here is a view on the South side, facing North, of the East end as well; the other side from the above image:

11/12/2019, South side, East end. Outer braces highlighted in blue.

And there it is. My “W” moment. The cross braces form “arrows” which always point West. Looking at some images in my collection which I previously could not determine the side confirmed my suspicion. Here is an image from ca 1946:

A view from below, ca 1946 or 1948. I have highlighted the outermost cross braces. I now know this shows the locomotive facing a westerly direction.

Note the side bracing, which I have highlighted in blue, pointing to the West! I have a few other images that I unfortunately don’t have permission to share here, which further confirm my suspicion. So, for anyone who is attempting to identify an old image of the Trestle, if you are curious which side you are looking at, just look for the outer bracing to “point” you the way. 🙂