It is the site of one of the first U.S. Navy Yards, which served the American fleet for 174 years before closing in 1974...
It is also the site of a wonderful memorial to one of the first Black units mobilized during the Civil War (I was privileged to meet some of the reenactors of this unit during my Civil War reenacting days - nice bunch of guys). The memorial looks like this:
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It is also the home of the 3rd Judge Advocate General Detachment of the US Army Reserves.
So, Where Am I?
1st to give an answer - in the comments section of this post, gets a case of Girl Scout cookies sent to your Hero, or you can elect to have them sent in your name to a Hero in need.
Good luck!
UPDATE: OK, somebody needs to give Margaret a run for her money! She's one smart cookie, and quick on the draw, and correctly guessed that I am, indeed in Boston - home of the 54th Massachusetts Infantry Memorial, the Charleston Navy Yard, the 3rd Judge Advocate General Detachment, and a whole host of other historical sites.
And speaking of cookies, Margaret - where do you want that case sent?