Old Burying Ground in Harvard Square. My wife and I went to Boston once and visited the cemetery of Paul revere. I love the old slate headstones- especially the ones with skulls, skeletons, or gargoyles.
Headstone that is said to have been the inspiration for Nathaniel Hawthorne's image of The Scarlet Letter. Site located near King's Chapel in Boston's oldest burying ground and was founded in 1630 at the time of the settlement of Boston.