Gotham City Jail is a medium sized containment facility for captured offenders located in central Gotham City. The Jail is usually used for criminals awaiting trial, who are then, if found guilty, transferred to either Stonegate Penitentiary or Arkham Asylum respectively depending on their state of mind.
While he was being investigated for allegedly accepting bribes from Rupert Thorne, Commissioner Gordon was a detainee in the City Jail. He was busted out in a mock escape to try and further incriminate him in the joint scheme of Gil Mason and Two-Face. However their plan was ultimately foiled by Batman, Robin and Batgirl.