Bad weather keeping you indoors? Check out this cool photo of the Smithsonian Castle from 1900 and explore the rest of the Washingtoniana Collection at the D.C. Public Library. Plus, related articles from SI.edu and Ghosts of DC.

Take a look at the proposed Executive Mansion to be built on Meridian Hill, a plan championed by Mary Foote Henderson. See the extravagant design, plus learn more about Mrs. Henderson and other buildings that were never built in Washington.