a point near Maidstone, when it turns north. Here it breaks through the North Downs at Rochester before joining the River Thames as its final tributary near Sheerness. The river is tidal as far as Allington lock, but in earlier times cargo-carrying vessels reached as far upstream as Tonbridge. The Medway has captured the head waters of other rivers such as the River Darent. There are other rivers in Kent, most notably the River Stour in the east. Hills Flora and fauna The wide range of habitats in the area gives the county a rich variety of Kent's plant and animal species. These habitats are the consequence of a combination of several different factors including climate, geology, relief and land use. A number of organisations exist in the county to help conserve the landscape and wildlife which lives within it. More than 60 nature reserves are managed by Kent Wildlife Trust. Kent houses a significant number of internationally important sites, including Special Protection Areas, Ramsar wetlands, Special Areas of Conservation, Sites of Special Scientific Interest, national nature reserves, Environmentally Sensitive Areas, local wildlife sites, roadside nature reserves, and Areas of Outstanding Natural Beauty. Kent Wildlife Trust manages the Local Wildlife Sites system in Kent, and manages over 60 wildlife reserves over the county of Kent. Access is free and visitor centres provide educational programmes to children and adults alike. References