One of the last two ancient church burying grounds left inside historic Paris, Calvaire cemetery is located on the heights of Montmartre, just a stone's throw from Sacre Coeur.
The cemetery is open only one day a year, however, 1 November, All-Soul's Day.
The other old church burying ground? Charonne in the 20th arr. near Pere Lachaise.
This image is taken from a tiny corner in this very tiny cemetery.
That's right Marie B. has found Fresnel's grave in Division 14 of Pere Lachaise. I recall looking for him probably a dozen times -- and eventually involving Marie and, I think even Philippe in the search for his grave.
Who is Fresnel and why should we care? For an answer to the first half of that question, check out what Wikipedia says.
As for the second half, well I suppose it's because of his work in developing the lens used in virtually every lighthouse in the world!