The Coromandel Peninsula juts north of Auckland into the Hauraki Gulf, with a rugged mountain spine dividing the west coast (sheltered) from the east (Pacific Ocean beaches and pohutukawa trees). The circuit via the scenic SH25A over the peninsula's high point offers both coasts. Hot Water Beach and Cathedral Cove are iconic.
Clone it to your planner, customize dates and stops, then ride. All free.