Information on GNC in New Castle, DE 19720 Outlet Note Regular Brands GNC Delaware New Castle 328614 Rating 4.7 based on 97 votes Address 2034 new Castle Avenue New Castle, DE 19720 Phone Hours may vary in different stores. For accurate hours, please contact each store directly. Suite643 Hours may vary in different stores. For accurate hours, please contact each store directly. Nearby GNC Outlet GNC Outlet - New Castle GNC Outlet - Wilmington GNC Outlet - Newark GNC Outlet - Bear People Also Viewed