Claremont Square Reservoir

Water was pumped from the New River Head (q.v.) to the new reservoir, which had a sluice-house to the south. As the area became increasingly populated, the water needed to be raised an additional 30 feet and a huge cast-iron pipe in the shape of an inverted U was erected, apparently to the mystification of passers-by. The reservoir was railed and had garden walks around it only accessible to the privileged few. At one time on a hill adjacent to the reservoir and with views towards the City was a C17th pleasure ground with a railed bowling green and Busby's Folly, a tearoom that later became the Belvedere Tavern. In the 1830s the tavern had gardens with gravelled walks, the remains of the old bowling green and a racket court behind it that was in use until the tavern was rebuilt in 1876.

In 1821-28 four terraces that comprised Claremont Square were erected around the reservoir when the New River Company began to develop their estate for housing. The name Claremont derives from the mansion in Surrey where the then Prince and Princess of Wales went to live in 1816. In the 1850s the New Reservoir, together with the Round Pond at New River Head, was drained and the water piped, covered and turfed following the 1852 Metropolis Water Act that decreed that no standing water could remain uncovered in the London area. The hooped pipe became redundant and the central area was raised and enclosed by a high brick wall, the former reservoir becoming a high flat-topped mound with steep sides. In 1885 local resident John Cross of 4 Mylne Street complained to the New River Company about its neglected appearance, describing it as 'a large enclosure containing a mound which...is planted with grass and a few shrubs, the seeds of which apparently dropped there by accident in some past age'. His suggestion that it 'might be made very pretty, and a great pleasure to the thousands of people who pass by it every day' appears to have fallen on deaf ears.

Today the north side of the square is cut off by Pentonville Road; the railed central area is of interest for nature conservation, having good neutral grassland and diverse wild flowers. Exotic shrubs, laburnum and sycamore are planted at the base of the reservoir's sloping sides and to the west is a colony of spiked sedge.