GGW just posted a piece today about GWU Archives releasing a bunch of photos (and related images) from the construction of Metro. https://ggwash.org/view/72588/gwu-relea ... hotographs
Their existence was made known of on reddit.com/r/washingtondc/ last Wednesday
Direct link to George Washington University Libraries at archive.org
They are scans of 35 mm slides taken by various WMATA staff photographers in the 1970s and 80s of the construction digs, architectural renderings and models, The scans average around 4.75 mb, I haven't gone through all of them yet but I guessing there is around 2,000 inages. This collection is a small fraction of the total number of pictures taken by the same photographers during that era.
The C-5 collections are of Rosslyn from early excavation during mining to running of test trains.
John in the sand box of Maryland's eastern shore.