Imagine being a 4-year-old child and spending an hour on the bus to go the Allegheny County Jail to visit your father behind a glass partition.

Imagine sitting another hour-and-a-half in a drab gray lobby for the visit, and a jail guard admonishing your tense mother whenever you run around.

To alleviate some of the stress of the ordeal, the county jail this fall will become more child-friendly by opening a Family Activity Center, complete with a ball coaster, craft area, video nook, climb-and-slide and mock visitation center. A resource center there will provide information to parents and caregivers for helping some of the 7,000 children in Allegheny County who have a parent behind bars.

During a ceremony outside the jail yesterday, Warden Ramon C. Rustin and others unveiled drawings of the center that they hope will become a national model.

"It is easy for critics to say, 'Why would you do this in a jail?' I say, 'Shame on us if we don't do this,' " county Chief Executive Dan Onorato said.

Sometimes people ask Claire A. Walker, executive director of the Pittsburgh Child Guidance Foundation and a leader in the project: "Why make a jail a fun place? Isn't that sending the wrong message to kids?"

She replies: "The more a child copes, the more likely they will become a coping adult. They are coping with the reality of losing a parent."

Ms. Walker knows of no other children's center in a waiting area of another jail or prison, but there are a handful in visitation areas. The high-rise design of the Allegheny County Jail, with eight separate visiting areas, makes the wait particularly long and hard on children, most of whom are younger than 6.

The family center will not have bright colors or cutesy characters, but will be done in soothing blues and greens and occupy about half of the lobby. Architects of the Strip District firm of CDM visited the new Children's Museum to get ideas, but had to modify their ideas within the tight security requirements of a jail.

"Everything had to be contained," architect Ed Roethlein said. "No markers. No crayons. You can't have paper-cutting."

The new jail area is a joint project of the Pittsburgh Child Guidance Foundation, county Bureau of Corrections and Lydia's Place. It is being financed with $50,000 in county funds, plus $150,000 from foundations, including the Heinz Endowments and The Grable Foundation.

Donations from individuals, including Eric and Amy Mallinger, 13-year-old twins from Squirrel Hill who gave about $200 of the money they got from their bar and bat mitzvahs to buy stuffed animals, puzzles and books for the jail, also will be used.