Subway, the 37,000 restaurant sandwich synonymous with its iconic $5 footlong subs, is taking a bold step into uncharted territory with their $5 Doritos footlong nachos.

A new foot-long snack option has appeared on Subway menus in the U.S.: the 'Doritos Footlong Nachos.' They will stay on the menu 'for a limited time while supplies last,' the restaurant chain said.

Subway's latest creation seems like a big departure from anything else the sandwich chain offers. Here's what to know about Subway's Footlong Nachos and how to get one for free.