The Observatory (grid reference ST564733) is a former mill, now used as an observatory, located on Clifton Down, close to the Clifton Suspension Bridge, Bristol, England. At 337 feet (92 metres) above the gorge, the cliff top is likely to have been used as a lookout post since at least the Iron Age.
The building was erected with the permission of the Society of Merchant Venturers, as a windmill for corn in 1766 and later converted to the grinding of snuff, when it became known as 'The Snuff Mill'. This was damaged by a fire on October 30, 1777, when the sails were left turning during a gale and caused the equipment to catch light. It was then derelict for 52 years until in 1828 William West, an artist, rented the old mill, for 5 shillings (25p) a year, as a studio.
In 1977, the Merchant Venturers sold the observatory to Honorbrook Inns, however they were obliged to maintain public access to the camera obscura whose ownership was retained by the Merchant Venturers.
It has been designated by English Heritage as a grade II* listed building and is currently on the Buildings at Risk Register.