The Wentworth Bunker was an extensive underground fallout shelter retrofitted to serve as the headquarters of Arsenal and Nightwing's Outsiders group until the location's security came into question and it was subsequently demolished.
The headquarters contained many advanced technology systems in addition to a conference room mainframe, advanced training room, medical facilities, room and board for the team's members and hangar facitlies for the Pequod battle cruiser.
C.T. Wentworth, a multi-millionaire electronics magnate who made a ton in the 1950's and 1960's, was paranoid about a nuclear holocaust in the 1950's and built an extensive shelter 1,273 feet below Brooklyn that stretched beneath 9 city blocks.
When he died, the shelter was listed simply as "Brooklyn Bomb Shelter" and forgotten. Taking the offer by Optitron to fund his activities, Arsenal uses the acquired funds to buy the shelter and renovates it to serve as the base of the new Outsiders team.
Breached multiple times by allies like Metamorpho and Black Lightning, and enemies such as Shrapnel. After Indigo's transformation into Brainiac 8 and the decimation of the bunker, Arsenal scuttled the headquarters and made the group mobile.