Northern Kentucky shares borders with the states of Indiana and Ohio and much of the region's identity is influenced by the close proximity of Cincinnati, situated directly across the Ohio River. Northern Kentucky encompasses a total of 13 counties and several key cities, including Newport, Covington, Erlanger and Independence, most of which are considered to be part of Greater Cincinnati. Newport offers visitors a striking view of the Cincinnati skyline and lures many tourists to premier attractions, such as the Newport Aquarium, Newport on the Levee and the World Peace Bell. Covington is recognized for housing the Roman Catholic Cathedral Basilica of the Assumption and the historic architectural attraction, Holmes High School, originally built as a castle in the late 1800s. Rolling hills and farmland blend to form the Northern Kentucky landscape and many farm and eco-tours can be attributed to the large amount of agricultural industry in the area.