These two formal ponds date from the 1720s when the 3rd Earl of Carlisle, together with Vanbrugh and Hawksmoor, were turning their energies towards designing the extensive Castle Howard landscape, filling it with a spectacular array of monuments and planting thousands of trees, including the Limes that line the Avenue. Water was also an essential part of this vision, as the natural streams and springs that riddle the area were exploited for more ornamental purposes. The South Lake was fashioned in 1724, and a system of fountains and cascades was laid out inside Ray Wood. The two formal Obelisk Ponds, looking rather like small canals, were part of this phase of design, and first appeared on an estate map of 1727.

They owe their appearance to an enduring fashion for formal water features, defined by precise geometry and symmetrical shapes, and mirror similar constructions elsewhere in the country. They are attributed to the garden designer and engineer Stephen Switzer, who was renowned for his work at places such as Grinsthorpe Castle, Lincolnshire, and Bramham Park, Yorkshire, where this is a similar series of ponds and pools. It would be nice to attribute these Obelisk Ponds definitively to Switzer, who is known to have visited Castle Howard, but there is no record in the archives of him receiving payment here. If he was not directly responsible for the creation of these two ponds he will undoubtedly have advised on their construction.

These two pools are connected to a series of ponds and streams further west which feed them, thereby ensuring a constant water supply that will maintain their levels. The western pond is fed through a rustic cascade from the pond the other side of the bridge, the water then drops into the eastern pond flowing through the central arches beneath the bridge on the Avenue.

In recent years both ponds were incapable of holding water for any length of time; the puddled clay that originally ensured a watertight seal had become degraded and damaged, and had sprung a multitude of leaks. The recent work has involved re-shaping the ponds, defining the banks and their gradients; introducing new clay which has been puddled, or compacted, and creating a uniform depth; at the same time mechanisms have been installed for regulating the inflow and outflow.

Today, instead of a nondescript view of two ponds that were largely empty, silted up, and filled with unsightly vegetation, the sharply delineated lines of the banks create a pair of rectangular lagoons with wonderful reflective properties. The recovery of these ponds makes crossing the bridge an experience in itself, with the uniform water surface and views beyond stretching out in either direction. Like so much of Castle Howard it is the experience of moving through the landscape that counts most, as the eye is stimulated by an array of features – buildings, trees, distant vistas, and water.