Clara Maass is an OMNIA Tier 1 facility. 50 Newark Avenue is located on the campus of one of New Jersey's OMNIA Tier 1 hospitals...Clara Maass Medical Center. RECENTLY NAMED: 2016 Best Renovated or Repurposed Healthcare Facility ,this beautiful building is located steps away from Clara Maass Medical Center, making it a great opportunity for a physician who is looking to be within close proximity of the hospital. It has also recently undergone many new renovations and improvements. Located in Belleville, NJ, hugging the boarders of suburbia and the city, Clara Maass Medical Center is a community hospital that offers patients expert care in a technology-rich environment, close to home. Nicknamed "Hospital in the Park", because if its close proximity to lovely Branch Brook Park, Clara Mass Medical Center is a 469 bed facility serving residents of Essex, Hudson and Bergan Counties.