New River Head is a historic site located adjacent to Sadler's Wells Theatre on Rosebery Avenue and Amwell Street in the Clerkenwell area of London, England.

At the rear of the building (not open to the public) there is the remains of the medieval conduit-head of the water supply of the London Greyfriars, discovered in Bloomsbury in 1911 and re-erected here in 1927.

It was subsequently passed to Thomas Howard, 4th Duke of Norfolk, and eventually to Samuel Backhouse who, along with his son John, was one of the original "adventurers" (shareholders) of the New River Company.

[10] In 1708, a new Upper Pond was constructed on higher ground where Claremont Square lies today, in order to give a better head of pressure to serve more distant areas around the West End of London.

Initially water was pumped to this from the Round Pond by windmill and horse gin, but in 1768 a steam engine designed by John Smeaton was brought into use.

[10] Between 1915 and 1920, the Metropolitan Water Board, as successor to the New River Company, constructed a substantial new head office building on the Rosebery Avenue side of the site and across the, by now redundant, Round Pond.

In 1946, the London end of the New River was truncated to Stoke Newington with the water being fed into the East Reservoir there, thus removing the operational usage of the site.