Highclere Castle /ˈhaɪklɪər/ is a Grade I listed country house built in 1679 and largely renovated during the 1840s, with a park designed by Capability Brown in the 18th century. The 5,000-acre (2,000-hectare) estate is in Highclere in Hampshire, England, about five miles (eight kilometres) south of Newbury, Berkshire, and 9+1⁄2 miles (15 kilometres) north of Andover, Hampshire. The 19th-century renovation is in a Jacobethan and Italianate style produced by architect Charles Barry. It is the country seat of the Earls of Carnarvon, a branch of the Anglo-Welsh Herbert family.
Highclere Castle has been used as a filming location for several films and television series, including the 1990s comedy series Jeeves and Wooster. It achieved international fame as the main location for the ITV historical drama series Downton Abbey (2010–15) and the 2019, 2022 and 2025 films based on it.