Monkey Island Estate is a small private island on the Thames at Bray, Berkshire, now a luxury hotel built around two 18th‑century Palladian pavilions created as an angling retreat for the 3rd Duke of Marlborough, layered over a site first used by monks in the Middle Ages.
It is reached by a pedestrian footbridge and is occupied by landscaped lawns, riverside walks, and the historic Temple and Pavilion buildings, now embedded in a wider hotel complex.
The site appears in records from the 12th–13th centuries as “Monks Eyot”, when Augustinian monks from nearby Bray or Merton Priory used it as a fishing and produce outstation.
The island passed to the Englefield family in the early 17th century and was bought in 1738 (sometimes dated c.1723 in secondary retellings) by Charles Spencer, 3rd Duke of Marlborough, a keen fisherman who wanted a private angling retreat. Reworked over the years traces of its history remain.
 
Interesting fact...
The island is largely composed of demolished London from after the Great fire. Barges deposited the waste on the much smaller island creating the landscape we see today - literally built on London.
Why is is called Monkey Island? no one really knows but there certainly aren't any monkeys living there!