Queen ant's hatchery is a cave system that can be accessed from Marigold station.
The ants here are mutated fire ants, created by Doctor Lesko in a failed attempt at reducing their size. You will be sent here during the quest "Those!". On Doc Lesco's desk/table can be found a filtration/containment unit, within which can be found a sample of his own mutated strain of the FEV virus.
The hatchery is entered through a depression in Marigold station's Blue Line. A large portion of the cave is a winding trail that descends further into the ground. Five fire ant nest guardians are along the route. At the bottom of the trail, the cave opens up into a large chamber with the Marigold ant queen. The chamber also contains a terminal with the capability to destroy the fire ants in the Grayditch area. A small portion of the trail continues around behind the large chamber allowing the player to see the chamber safely from behind a rock column.
- Five fire ant nest guardians and the Marigold ant queen
- Doctor Lesko's protectron
- Doctor Lesko
- Big Book of Science in the Marigold ant queen's chamber.
- Nuka-Cola Quantum in the Marigold ant queen's chamber.
- Ant nectar inside ant refuse piles.
The queen ant's hatchery appears only in Fallout 3.