Althorp is a Grade I listed stately home and estate in the civil parish of Althorp, in West Northamptonshire, England of about 13,000 acres (5,300 ha). By road it is about 6 miles (9.7 km) northwest of the county town of Northampton and about 75 miles (121 km) northwest of central London, situated between the villages of Great Brington and Harlestone. It has been held by the prominent aristocratic Spencer family for more than 500 years, and has been owned by Charles Spencer, 9th Earl Spencer since 1992. It was also the home of Lady Diana Spencer from her parents' divorce until her marriage to Charles, Prince of Wales.

West Northamptonshire is a unitary authority area covering part of the ceremonial county of Northamptonshire, England, created in 2021. By far the largest settlement in West Northamptonshire is the county town of Northampton. Its other significant towns are Daventry, Brackley and Towcester; the rest of the area is predominantly agricultural villages though it has many lakes and small woodlands and is passed through by the West Coast Main Line and the M1 and M40 motorways. The district includes the site of the Roman town of Bannaventa, and the grade I listed Althorp House and its estate.