Lancelot Brown (1716–1783), more commonly known as 'Capability' Brown, is arguably one of England's greatest landscapers. Brown worked at Euston Hall between 1767 and the 1780’s where he created fashionable landscapes containing weirs, pools and rivers.
In 2013, these were dredged and restored to their former glory, using Brown’s original waterway plans. Two of his original landscaping plans for Euston are displayed within the Hall, however, the full extent of his work is not known.
The watermill was built by Sir Samuel Morland in the 1670s for Lord Arlington and supplied by a man-made lake, via a canal. Its purpose was to pump water to the fountains and the Hall, as well as being used for grinding corn. It was redesigned in 1731 by William Kent, who styled it after a church.
An iron waterwheel was added in 1859 in the bricked up section next to the main door and supplied by the well-known engineering firm of Charles Burrell of Thetford. The 11th Duke of Grafton completely restored the building with the assistance of English Heritage during 2000 and 2001.