Limoux is a city in France.
Onboard the Bus, Leo Fitz and Jemma Simmons discovered that the design of the weapon they retrieved on Jamaica was Chitauri-inspired but augmented with Overkill tech. Skye was able to hack the weapon's code and track its origin to a remote town in France.
The Bus flies to the town of Limoux where the agents find themselves in the middle of the Tour de France. After locating the house and entering, the team was ambushed and Fitz was captured and taken to Antarctica.