Chichester Harbour Area of Outstanding Natural Beauty (AONB) is a tidal estuarine environment, framed by low-lying coastal plain against the backdrop of the South Downs National Park. The Harbour's coastline is charactarised by distinctive tidal channels leading to a maze of inlets and rithes that criss-cross expanses of saltmarsh and mudflats. The shoreline is fringed by wind-sculpted oaks and scrub, with open agricultural fields bounded by hedgerows. Historic coastal villages are defined by centuries of maritime association, and in the flat landscape, the vertical elements of church spires and old mills are an important part of its character.
The landscape character is shaped by the patterns of sea and land changing with the tide, weather and seasons. The dynamic landscape is constantly changing in response to natural processes and human activities. Agriculture has developed; settlements have changed in both their appearance and extent; roads and traffic have increased and the industries associated with the Harbour have changed. Natural events, such as Dutch Elm disease and storm events have also had a significant visual impact, with the loss of many of the characteristic, wind-shaped trees and woodlands.