Washington National Cathedral (Cathedral Church of Saint Peter and Saint Paul)

Construction of the Washington National Cathedral began in 1907 and continued through much of the 20th century, with major completion milestones culminating in 1990, making it a prominent example of Gothic Revival architecture in the United States. The cathedral's exterior and interior feature carved stonework, flying buttresses, and detailed tracery modeled after English medieval cathedrals. Among its notable architectural features is the 'Space Window,' a stained-glass window that includes a fragment of lunar rock from the Apollo 11 mission.