In October, we celebrate various holidays like Columbus Day and Halloween. But none of these can stand up to the greatness of Submarine-Hoagie-Hero-Grinder Day, which happens to be today, October 9th. To celebrate the day of the sandwich, we thought we’d take a look at the submarine, the hoagie, the hero, and the grinder, and explain the provenance of these very similar creations. Before we get started, let’s just note that these are all basically the same delicious stuffed-to-the-gills, full-loaf Italian deli meat, cheese, and vegetable sandwiches. The real story lies in how the sub came to be known by a variety of monikers throughout the U.S.

Click through the gallery to find out the origins of the submarine, the hoagie, the hero, and the grinder.