When the Duke of Buckingham ordered his York House (approximately located at present day 38 Strand) to be modernised in 1623, “it was customary for nobility to be conveyed by water”  while the less convenient carriages were preferred for state purposes. This made the building of private watergates by the river very common in noblemen’s houses, “and stairs led from the grounds to the water-side, for the convenience of taking boats.”
Long thought to have been built by Inigo Jones (1586-1647), it is today believed that this gate is the work of the appropriately named master-mason Nicholas Stone (1586-1647). It is one of the few remaining examples in London of this bold, strong Italianate style typical of the reign of Charles I. 
The door is today mostly seen from the river side of the park, which must have been (purposely) impressive to visitors with its large Portland stone archway upon steps and lateral apertures, the huge keystones, and its four heavily rusticated (textured) doric columns.
The ornamentation makes use of Villiers (the Duke of Buckinham’s family name) heraldry: escallops in the frieze, lions, shields and anchors — all reference to the Duke’s admiralship. The Villiers arms are proudly shown in the curved pediment in the centre, using the Renaissance language of architecture: in a carved cartouche (ie. a tablet in a scroll-like frame) surmounted by another large escallop, the family’s cross and five escallops are encircled by the riband of the order of the Garter and the ducal coronet.
The Northern side, that is, away from the river and facing towards where the house stood, is the soft — almost charming — complement to the South facade: the three arches are now of equal height, separated not by columns but by unornamented pilasters, with the elevation not being as dramatic as its southern counterpart. The keystones are now marked with ornamental shields: in the centre one finds the arms of the Villiers family, and on the sides the traditional anchors. Finally, Buckingham’s motto is carved on the frieze: in latin, “The Cross is the Touchstone of Faith”.
Just like his colleague Inigo Jones, Nicholas Stone was widely influenced by Sebastiano Serlio and Andrea Palladio, especially by the former’s more daring and vivid style (that we would today associate with Mannerism), which frequently resorted to dramatic rustication and depth variations.
The picturesque effect of this grand door was greatly reduced by the creation of the Thames Embankment which pushed the Thames’ waters 137m down. As W. Hutchings wrote in his 1909 London Town, “the presence of this beautiful structure helps one realise the difference which has been made by the creation of the Embankment, for whereas now it is some hundreds of feet away from the river, the steps at its base used to be lapped by the tide.”
There is unique picturesque quality to the watergate today: it stands here, isolated, deprived of its original function, poetically reminding to the wanderer of the past, when its stones were still freshly carved, when York House was still standing, and when the Thames splashed its base.
 John Britton and Augustus Pugin, Buildings of London, London : J. Taylor, Volume II, 1826, p. 39
 G H Gater and E P Wheeler (ed), Survey of London: Volume 18, St Martin-in-The-Fields II: the Strand, London, 1937, Plate 32
 W. W. Hutchings, London Town past and present, New-York: Cassell, 1909
 James Stevens-Curl and Susan Wilson, The Oxford Dictionary of Architecture, Oxford University Press, 2016 (3rd Edition)
Paul is a Physics student at King’s College and has been captivated by London’s unique artistic and architectural heritage ever since arriving in 2015.