I’ve always kept an eye out for photos showing freight cars at the Lincoln Memorial, as all of the stone for the Memorial was brought down the Georgetown Branch and onto a temporary branch extension that was laid from the end of the GB, across Rock Creek, down along the Potomac River and over to the construction site. The cornerstone was laid on Feb 12, 1914 so one can reasonably assume that track was laid at some point the previous year when construction began on the massive footings. Foundation work was completed in 1915 and work continued steadily until the Spring of 1917 when the US entered WWI. In Dec 1919 & Jan 1920 the Lincoln statue was assembled. The dedication was on 5/30/1922. So, for roughly ten years the GB was extended to the work site, bringing in the massive marble blocks and pieces needed for one of the most impressive monuments in the US. Pretty neat!
Photos of the construction site are plenty, but rarely focus on the railroad apparatus and right of way that served the site. I have only found a few images and am still uncertain as to the exact alignment of the tracks and yards there. I imagine they would reconfigure to some degree as time went on. Eventually the site around the monument would be filled in with dirt, covering over all of the construction yards surrounding the monument. So recently I found an image which has a couple freight cars visible. I’ve zoomed in on these to highlight the details.