The Bikini Bottom Jail is a governmental institution in Bikini Bottom as seen occasionally in the series. It was first seen in the episode Hall Monitor.
The building is two stories high, with an over-sized ball-and-chain attached to it. The prison features a rock crushing yard, cafeteria, and the jail cells. The inmates do many activities such as crush rocks, lift weights, and make wire hangers and license plates. There have been many instances that involved main characters going to jail.
A solitary confinement room supposedly made of sponge. (This may not be entirely accurate as Mrs. Puff was delusional at the time.)
A coat hanger factory. (This may be a reference to the cliché of a license plate factory being in prisons.)
A plankton-sized prison cell, actually a safe, seen in "Krabby Road".
A cafeteria that supposedly only serves chili.
A water supply that supposedly contains high amounts of uranium. (This may be a reference to the recent worry of mercury-contaminated water. This may also be a reference that Bikini Atoll, the location of Bikini Bottom was the site of 67 nuclear tests done by the U.S. government in the 1940s and 50's.)
Mrs. Puff has been in jail in "Hall Monitor", "No Free Rides", "Ditchin'", "Summer Job", and "Doing Time. In "Hall Monitor" and "Doing Time", Mrs. Puff was sent to jail because SpongeBob destroyed Bikini Bottom. In "No Free Rides", she stole SpongeBob's new boatmobile and crashed it into a police car. In "Summer Job", she was going to be sent to a Stoney Lonesome in the same outfit as "Hall Monitor". And in "Ditchin'", she was sent to jail because she skipped Jury Duty. It was also implied that she was going to jail in "Patrick Man!". Patrick thought she was breaking into a boatmobile (when in reality, she was trying to help one of her students was locked inside and couldn't get out.). He threw a net over her, and left a note which read "Kops-This is boat theef". She was thrown into a paddy wagon, and one of the police asked her if she remembered what a felony was.