The gardens were designed by Henry Hoare II and laid out between 1741 and 1780 in a classical 18th-century design set around a large lake, achieved by damming a small stream. The inspiration behind their creation were the painters Claude Lorrain, Poussin and, in particular, Gaspar Dughet, who painted Utopian-type views of Italian landscapes. It is similar in style to the landscape gardens at Stowe
Included in the garden are a number of temples designed to show off the Hoare family’s education and wealth. On one hill overlooking the gardens there stands an obelisk and King Alfred’s Tower (a 50-metre-tall, brick folly designed by Henry Flitcroft in 1772); on another hill the temple of Apollo provides a vantage point to survey the magnificent rhododendrons, water, cascades and temples. Amongst the woodland surrounding the site there are also two Iron Age hill forts: Whitesheet Hill and Park Hill Camp. The gardens are home to a large collection of trees and shrubs from around the world.
Richard Colt Hoare, the grandson of Henry Hoare II, inherited Stourhead in 1785. He added the library wing to the mansion and in the garden was responsible for the building of the boathouse and the removal of several features that were not in keeping with the general classical and gothic styles (including a Turkish Tent). He also considerably enhanced the planting – the Temple of Apollo rises from a wooded slope, that was planted in Colt Hoare’s time. With the antiquarian passion of the times, he had 400 ancient burial mounds dug up in order to inform his pioneering History of Ancient Wiltshire