This is a list of Sites of Special Scientific Interest (SSSIs) in Northumberland, England.
English Nature, the designating body for SSSIs in England, uses the 1974-1996 county system, and this list follows the same approach. Some sites one may expect to find here could therefore be in the County Durham or Tyne and Wear lists.
For other counties, see List of SSSIs by Area of Search.
The River Coquet runs through the county of Northumberland, England, discharging into the North Sea on the east coast at Amble. It rises in the Cheviot Hills on the border between England and Scotland, and follows a winding course across the landscape ("Coquetdale"). The upper reaches are bordered by the Otterburn Ranges military training ground, and are crossed by a number of bridges built in the 20th century. It passes a number of small villages and hamlets, and feeds one of the lakes created by extraction of gravel that form the Caistron Nature Reserve, before reaching the town of Rothbury, where it is crossed by a grade II listed bridge. Below the town is Thrum Mill, the restoration of which was featured on Channel 4 television.
Holystone is a small village and former civil parish, now in the parish of Harbottle, in Northumberland, England. It lies on the edge of the Northumberland National Park on the north bank of the River Coquet. A significant landmark is Holy Well, traditionally the site of early Christian baptisms, and the source of Holystone's water supply. In 1951 the parish had a population of 71.
The North Northumberland Coastal Plain is a major natural region that lies on England's northeasternmost stretch of coastline on the North Sea. To the west lie the Cheviot Fringe, the Northumberland Sandstone Hills and Mid Northumberland; to the south it is continued by the South East Northumberland Coastal Plain.
The Northumberland Sandstone Hills are a major natural region in the English county of Northumberland. The hills form distinctive skylines with generally level tops, northwest facing scarps and craggy outcrops offering views to the Cheviots further west.