Parking garage where Washington Post reporters Woodward and Bernstein met with informant Deep Throat to get information on the Watergate break-in. The information eventually led to the resignation of President Richard Nixon in 1974.
The specific parking space the meetings took place in was number 32D.
Wikipedia article:
http://en.wikipedia.org/wiki/Deep_throat#Secrecy_was_keyCategory:
politics historic interesting place