Northwood had a manorial grange in 1248, which may have occupied the site of the later Northwood Grange. The monks of the Bec Abbey who lived at Manor Farm in Ruislip in the 11th century owned this grange. A few cottages at Northwood are mentioned in the 1565 national survey. Two hundred years later the shape of the hamlet, composed of a few farms and dwellings scattered along the Rickmansworth road, had altered little except for the addition of Holy Trinity church. Robert Cecil, 1st Earl of Salisbury had of Ruislip cleared of forest.
Northwood had a manorial grange in 1248 which may have occupied the site of the later Northwood Grange. The monks of the Bec Abbey who lived at Manor Farm in Ruislip in the 11th century owned this grange. A few cottages at Northwood are mentioned in the 1565 national survey. Two hundred years later the shape of the hamlet, composed of a few farms and dwellings scattered along the Rickmansworth road, had altered little except for the addition of Holy Trinity church Robert Cecil 1st Earl of Salisbury had of Ruislip cleared of forest.