Shadyside is full of these little enclaves of townhouses, improbably narrow streets (or simply pedestrian walkways) that shut out the world and create their own little enclosed communities. Ellsworth Terrace, built in 1913, is a fine example of early-twentieth-century arts-and-crafts design. Wikipedia lists the architect as William H. Justice, but with a question mark after the name. The pseudo-Victorian building to the right is a much more recent condominium.