
Belsize Avenue was once the driveway to the former Belsize House.
Before suburbanisation the main drive leading to Belsize House (c.1500-1853) corresponded with the line of the present Belsize Avenue. The house itself had a substantial courtyard form and was surrounded by extensive gardens with views over London to the south. The surrounding land was in agricultural production with a combination of arable land and pasture supplying the capital.
Belsize Avenue was the scene of 18th century traffic jams when the grounds were used as a pleasure garden. Until 1835 a five-barred gate closed the east end of Belsize Avenue.
In 1852 Charles James Palmer, a Bloomsbury solicitor, bought the lease of Belsize House, with the intention of building. The Dean and Chapter of Westminster decided to retain control of the Avenue, keeping it undeveloped and so Palmer had to change his building layout plans.
A temporary fire station was established in Belsize Avenue during 1869, and in 1870 the Dean and Chapter finally gave Belsize Avenue to the parish of Hampstead, on condition of the vestry planting new trees as the old ones were failing.
Building, mostly by William Willett, finally proceeded on both sides of Belsize Avenue from 1871. The housing that still lines Belsize Avenue derives from the desire to develop large scale houses, set well back from the road retaining an avenue of trees along its length.
In her 1902 book "The Fascination of Hamsptead", Geraldine Mitton says: "Belsize Avenue is a park-like road, from which on the south side stretch the meadows of
Belsize Park. Large elm-trees of great age throw shade across the road, and seats afford rest to those climbing the ascent to
Haverstock Hill."
Due to a slump in this value of style of housing, houses in Belsize Avenue halved in value between the 1880s and the 1920s and 1930s.
Price have recovered somewhat!

Belsize Avenue in Belsize Park
User unknown/public domain
Rosslyn House Rosslyn (Roslyn) House, which stood between Wedderburn and Lyndhurst Roads, was one of the last of the famous old Hampstead houses to be destroyed. Shepherd’s Well Shepherd’s Well, whose flow was thought to be nearly as pure as distilled water, is the source of the River Tyburn. St Stephen’s Church St. Stephen’s is a former church building, sited on Rosslyn Hill at its junction with Pond Street, a steep slope adjacent to the Royal Free Hospital. Baynes Mews, NW3 Baynes Mews is a mews within the conservation area of Belsize Park. Belsize Lane, NW3 Belsize Lane is a thoroughfare linking Rosslyn Hill with Swiss Cottage. Cressy Road, NW3 Cressy Road was named for a famous English victory by its builder Thomas Gibb. Hillfield Court, NW3 Hillfield Court serves a prominent art deco residential mansion block of the same name in Belsize Park. Hillfield Court, NW3 Hillfield Court is a prominent art deco residential mansion block in Belsize Park, in the London Borough of Camden, built in 1934. McCrone Mews, NW3 McCrone Mews is a mews - formerly the location of a depot of the London Parcel Delivery Company. Rosslyn Hill, NW3 Rosslyn Hill is a road connecting the south end of Hampstead High Street to the north end of Haverstock Hill.
The Manor of Belsize dates back to 1317, with the name is derived from French bel assis meaning 'well situated'.Belsize Manor was built by Daniel O'Neill for his wife, the Countess of Chesterfield, in the 17th century. Urbanisation took place largely between 1852 and 1878, by which time it extended to
Haverstock Hill. After World War I, the construction of blocks of flats began, and now a great many of the larger houses are also converted into flats.
Belsize Park underground station was opened on 22 June 1907 by the Charing Cross, Euston & Hampstead Railway as an intermediate station on its line from Charing Cross to Hampstead. It is served by three lifts and there are 219 steps. The station was designed by Leslie Green and has his familiar facade of ox-blood faience with four round arched windows. It remained largely untouched until the late 1980s when the lifts were replaced and a new ticketing system installed.
It was during the 1930s that
Belsize Park contributed most to the artistic and intellectual life of Hampstead. Artists associated with the Mall studios included Dame Barbara Hepworth from 1927 to 1939, her first husband John Skeaping and second Ben Nicholson from 1931 to 1939, and Henry Moore, who lived at no. 11A Parkhill Road from 1929 to 1940. They were members of Unit One, a group of artists and architects founded in 1933 by Paul Nash (1889-1946), who lived at no. 3 Eldon Grove from 1936 to 1939. Sir Herbert Read, the poet and art critic, who lived in 1934-5 at the Mall studios, which he described as a 'nest of gentle artists', published the group's manifesto, a theory of modern style.
Another centre was no. 37
Belsize Park Gardens, meeting place of MARS, an architectural group, and home of Jack Pritchard, who founded Isokon, a firm making modern furniture designed by people like Walter Gropius and Marcel Breuer, refugees who brought a European dimension to the abstract design movement in the arts. Others included Piet Mondrian, the Dutch painter, who stayed with the Pritchards before moving to no. 60 Parkhill Road (1938-41). Pritchard also commissioned Wells Coates in 1934 to build the Isokon or
Lawn Road flats, partly to house artistic refugees, on a site which he owned. Built in concrete in a functional style, the flats came to be recognized as 'a milestone in the introduction of the modern idiom into London'.
In World War II, a large underground air-raid shelter was built here and its entrance can still be seen near the tube station at
Downside Crescent. The area on
Haverstock Hill north of
Belsize Park underground station up to Hampstead Town Hall and including part of a primary school near the Royal Free Hospital was heavily bombed.
Belsize Park these days is a lively area with many restaurants, pubs and cafés along
Haverstock Hill and also England's Lane.
Glossary:
A History of the County of Middlesex: Volume 9, edited by C R Elrington.