Castle Bank Address: 1725 S State St, Belvidere, IL 61008 Phone: (815) 544-6600 Banks Other Businesses: PNC Bank at 130 S State St, Belvidere, IL 61008 Alpine Bank & Trust Co at 600 S State St, Belvidere, IL 61008 Alpine Bank at 311 Logan Ave, Belvidere, IL 61008 BMO Harris Bank at 401 Southtowne Dr, Belvidere, IL 61008