Okay, someone needs to clue me in.
I believe that this promise bridge is the T Street Bridge that connects the unit blocks of T Street NW with T Street NE.
See this post from Prince of Petworth:
By: Prince Of Petworth 23 January 2012 10:05 PM
The Promise Bridge is on North Capitol Street connecting Bloomingdale and Eckington. Kinda reminds me of the love locks bridges in Paris. Not sure if the promise locks will be as popular.
