This is St Alfege's Park in Greenwich (and me looking sombre about something). As you can see, the park's perimeter is completely lined with headstones. I can't tell if the headstones have always been there, or if they were just relocated there when the cemetery was converted to a park (around 1889).
The place is quaintly atmospheric, but I have to say, my strange-o-metre clicked a few times when I saw the kids' play equipment, and it went off the scale when I saw the basketball court - both completely lined with headstones.
If you build it, they will come.