Old Post Office Pavilion (long periods of vacancy)

The Old Post Office Pavilion at 1100 Pennsylvania Avenue NW, completed in 1899, is a Romanesque Revival federal building that sat largely underused or vacant at various times during the 20th century. Multiple redevelopment proposals over decades left the building unoccupied for extended periods before an extensive private renovation converted it to a hotel and mixed-use facility in the 2010s. Its long cycles of vacancy and reuse are a well-documented part of its preservation history.