Ralph Allen, who developed the garden in the 1740s and 1750s, was an entrepreneur who supplied the ‘Bath stone’ that was being used to build the elegant terraces and crescents of the burgeoning spa resort. He constructed an early railway right next to Prior Park that allowed blocks of stone to be brought down into the city from the quarry at Combe Down.
The Palladian Bridge was built in 1755, elegantly hiding an otherwise pedestrian dam between two different water levels. This type of bridge – loosely based on designs by Andrea Palladio – was popular in England at that time, and other examples were built at Wilton House (1735) and Stowe (1738).
Allen was acquainted with Viscount Cobham, the owner of Stowe, and his circle, and one of them, Thomas Pitt, seems to have had a hand in the design of the Prior Park bridge – yet another example of the ‘liquid networks’ I have written about previously.
After Allen’s death Prior Park was sold several times and eventually became a school. The main house is still in use by Prior Park College, but the National Trust acquired the garden in 1993, and has been gradually restoring its various features ever since.