Richardson's ground squirrels spend the majority of their lives in underground burrows.  They hibernate underground for 4-8 months depending on age and sex, (see Hibernation) sleep underground during the active season, retreat underground to avoid inclement weather and many predators (see Predators and Parasites), litters are born and raised underground, and adults will even mate underground (see Reproductive Behaviour).

The burrow itself is a network of winding tunnels and chambers.  Burrow systems can extend up to 10m underground and go as deep as 1m.  A single burrow system has 5-7 surface exits, 2-5 grass-lined sleeping chambers, and a lavatory.

Each adult female Richardson's ground squirrel owns at least one burrow system, and commonly uses two different systems during a single season.  During one season a female ground squirrel will sleep in 8-10 different chambers, moving her litter with her.

Should a burrow system become vacated, it is soon taken over by neighbouring or dispersing ground squirrels.  Richardson's ground squirrels are very in tune with their surroundings, and will often begin investigating a burrow system within hours of its owner disappearing.  Consequently, a population reduction is often rapidly followed by reinvasion.

   

The hibernaculum (plural, hibernacula) is simply the chamber where a Richardson's ground squirrel hibernates.  Prepared 4-6 weeks prior to hibernation, the hibernaculum is not used as a sleeping burrow during the active season.  After immergence into hibernation, the hibernaculum is sealed off with a soil plug.  The only predator able to gain access to the hibernaculum is the badger.  (see Predators and Parasites)

The hibernaculum of a male ground squirrel is larger than that of a female, due in part to the larger size of males and also due to the vast amounts of food males store over the winter.  (see Hibernation)  As with normal sleeping chambers, the hibernaculum chamber is lined with dry grasses.