Sandy Bay is a small bay on the eastern Mediterranean coast of Gibraltar, on the opposite side of The Rock from the main city. It is situated to the south of Catalan Bay and is accessible via Sir Herbert Miles Road.
Directly above Sandy Bay and the Sir Herbert Miles coast road were Gibraltar's large Water Catchments which are no longer in use. The slope on which they sat is the Great Gibraltar Sand Dune, an ancient consolidated sand dune which dominates the Eastside of the Rock of Gibraltar. The dune's naturally smooth surface allowed for the construction of a water catchment area made up of a corrugated steel sheets and a layer of concrete. Rainwater flowed down the slope into an open channel which fed into the reservoir system inside The Rock.
In 1898, work began on four 5 million gallon water reservoirs which were cut into the western side of The Rock. They were officially opened by Governor George Stuart White in 1901. These reservoirs were fed by relatively small water catchment areas on the western side of The Rock.
The Water catchments above Sandy Bay were built in stages between 1903 and 1961, and were designed to cater for Gibraltar's ever increasing demand. The original plan was to cover an area of 10 acres (40,000 m2). Between 1911 and 1914 a fifth reservoir was excavated inside the Rock and the catchment area increased to 24 acres (97,000 m2). By 1961 the total catchment area had increased to its maximum of 34 acres (140,000 m2).
In 2001, the Gibraltar Ornithological and Natural History Society began to manage the phased work of dismantling this catchment construction. By 2006 the slope was entirely restored to its natural state and is now completely covered in vegetation native to this unique habitat of Gibraltar.