Northampton Square is on land owned by the Earls of Northampton from end 1500s to mid 20C. The area was known as Woods Close. Although it was effectively countryside until developed in the 1800s it was apparently not attractive. The area accommodated the main drove road to Smithfield Market, (St John Street), a sheepskin market, a lunatic asylum, and the water mains of the New River Company beside which nightsoil was deposited!
Discussions about development were already under way in the 1790s, when leases expired, but negotiations with the New River Company were tricky (details here). The diagonal line of Charles Street(map below) crossing the square was to accommodate the water main from the New River Head to the City. (The diagonal is now represented by a gap in the University buildings and present-day Sebastian Street.) This gave the square a ‘..pleasing dash..’, setting it apart from the other London squares!
The square was laid out in 1803-04 and built between 1805-13. Several builders were involved, although S P Cockerell, (the surveyor for the Northampton Estate), insisted on uniformity of outward appearance. The interior layout varies considerably. (Detailed discussion here.) The residents were initially tradespeople, particularly those in the clock, watch, and jewellery trades, and it seems the square has never been particularly cherished.
The style of housing in the square, with blind arcades and round window arches at ground floor, and blind arcades and round arches on the first floor, was repeated throughout similar developments in Clerkenwell and Islington in the 1820s.
I visited on a gloomy day and found the square rather depressing. The plane trees are large and probably date from the first planting of the square. Originally a private garden for the residents, the gardens were opened to public in 1885, with ‘..a new layout, central fountain, drinking fountain and iron urns..’ paid for by Charles Clement Walker, who also installed a drinking fountain in Wilmington Square.
The north side of the square is now unattractive University of London buildings.
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A walk which includes St John Street