Question: Which occurred first, St. Elizabeths Hospital being designated a National Historic Landmark or Sibley Memorial Hospital being a part of Johns Hopkins Medicine?
Sentence (from "Sibley Memorial Hospital"): Sibley Memorial Hospital is a non-profit hospital located in The Palisades neighborhood of Washington D.C. It is fully accredited by the Joint Commission on Accreditation of Healthcare Organizations, and is licensed by the District of Columbia Department of Health and Human Services.
Relevant evidence: Yes