English: Claremont square, Islington (4) Looking southwest at the south side of Claremont Square, Islington. The square was developed in the 1820s around the Upper Pond of the New River Company.

The New River is a man-made water channel which carried drinking water for 20 miles to London from the River Lee and Amwell Springs in Hertfordshire. It opened in 1613 and fed reservoirs in Islington. One of these, known as the Upper Pond, was built in 1709 beside Pentonville Road.

The reservoir in Claremont Square was covered and turfed in 1852 when open areas of standing water in London were prohibited by law. The reservoir is still in use by Thames Water. The semi-improved grassland on the top and sides of the reservoir supports a wide diversity of wild flowers and is a preserved habitat with restricted access.

In this photo, the bank of the reservoir is just visible on the right of the picture. See also [1] and [2] .