Rabbit hole

A rabbit hole is an object, generally massive in size, that Sims can enter or do activities in, but which the game camera cannot enter. Rabbit holes fade away when the camera gets closer to them, and Sims cannot be seen while they're inside one.

Rabbit Holes were one of the main reasons for The Sims 3's mixed reviews.

Functions
Most rabbit holes function as workplaces where Sims are employed and work in. Most of them are building-sized, though some of them, such as mausoleum, gypsy wagon, or arboretum are not. Sims can perform various activities inside rabbit holes, such as getting employed, attending a show, attending a class, and so on. Some rabbit holes give a lot assignment to community lots. A rabbit hole placed on a community lot will also replace the lot's map tag with the rabbit hole's map tags.

Some rabbit holes can be invested in, allowing Sims to become partners in them and own them. Sims who become owners can rebuild the lot to improve it so that it becomes more attractive, rename the rabbit hole, and also fire Sims at their will. They can't, however, fire the last employee who works there.

In some careers and professions, some of their duties or opportunities require entering certain rabbit holes to perform an activity. For example, firefighters sometimes have to respond to a building disaster in a rabbit hole. When Sims do this, they will just enter the rabbit holes and complete the tasks themselves, so exactly what they do doesn't really matter.

Although rabbit holes will fade when the camera gets closer, players can see their contents with cameraman view by pressing the Tab key. Everything inside the building is 2-D decorative textures that serve to make the rabbit holes or buildings more realistic when players peek through their windows from the outside. Environment sounds and music can be heard when Sims are inside the rabbit holes. Usually, that will be a sound effect related to the rabbit holes, such as a school bell at school or eerie voices at mausoleum, with audible background music.

Advertising deal
Sims who are at the top of Professional Sports career can do an advertising deal at the grocery or bookstore, which will reward them with §1,500 (good result), §500 (medium result), or nothing (failed result). How good the result is based on the Sim's mood. Sims can make another advertising deal 4 days after a successful deal or 1 week after a failed deal. Sims cannot have two deals at a time; which means they need to wait for a week to make a deal in a grocery if they've made one in a bookstore.

Autograph session
Sims who are at their top of Music or Professional Sports career can hold autograph sessions in some rabbit holes. While in an autograph session, Sims must give autographs to as many visitors as possible. The more Sims that get autographs, the more money the player will earn. Sometimes, this will also advertise to Sims, attracting them to enter the rabbit holes to watch a show or game, which will give an additional bonus. Technically, Sims can hold autograph sessions in rabbit holes that Sims can enter to attend a show or purchase items or services, i.e. theater, spa, diner, and grocery.

Multi-purpose rabbit holes
Since Late Night, some multi-purpose rabbit holes are present to preserve neighborhoods, such as Bridgeport, that lack enough space for big lots. Although this seems practical, there are some issues with multi-purpose rabbit holes, such as the inability to complete opportunities that are related to rabbit holes. Sometimes, the option to perform tasks from opportunities is not available, which prevents the player from completing the opportunities. For example, the afterschool activities-related opportunities cannot be completed at school in Moonlight Falls.