According to the Golden Legend, after his head was chopped off, St Denis picked it up and walked several miles, all the time preaching a sermon. The site where he stopped preaching and actually died was later made into the Saint Denis Basilica, which became the burial place for the Kings of France. Denis is also connected to the name of Montmartre, in French literally the mountain of the martyr, said to be the place where Romans executed Christians.
This walk has led to St Denis being depicted in art as headless, holding his mitred head in his hands. Handling the halo in this circumstance offers a unique challenge for the artist. Some put the halo where the head used to be; others have St Denis carrying the halo along with the head.
His feast day is October 9.