Courthouses in which criminal matters are handled also have jails. Visitors won’t usually see them, because they are typically located behind courtrooms, in the basement, or on a separate floor. These jails (sometimes called holding cells, bullpens, or “pens”) provide a temporary place to keep in-custody defendants while they wait for their cases to be heard. Most often, they are for day use only. But many county jails—where defendants await trial or serve non-prison sentences—are nearly as close to the courtroom as these holding cells; they’re often located immediately adjacent to the courthouse.