The War Memorial Hall, Wanganui, is considered to be one of the finest examples of New Zealand modernist architecture, and at the time of its construction in 1955-1960 was a radical departure from the norm for civic memorial buildings in New Zealand. The proposal to build a suitable memorial in Wanganui to those who had lost their lives in the Second World War was first formally suggested in 1945. Following the war, the government offered subsidies for the construction of war memorials around the country, with a strong preference for 'living memorials', such as community centres. The government offered the Wanganui Council £50,000 for the new memorial hall. The community raised the remaining money for its construction, which included contributions from the Returned Servicemen's Association and the Scottish Pioneers.

Eventually a site in Queen's Park, a reserve already incorporating public buildings and memorials (including the cenotaph and a memorial to those who had fallen in the New Zealand Wars of the 1860s), was chosen and a public competition was held in 1956. Selected from 42 submissions was the distinctively modern design of Gordon Smith of the Auckland architectural partnership of Greenhough, Smith and Newman. Construction began in 1956 and the building opened on Anzac Day, 25 April 1960. The final design was 'a white clean-lined floating block, a visual mass supported by set back concrete pilotis', all characteristics of the Modern style. Other characteristics of this style can be seen in the curtain-glass wall framed with concrete cube grilles at the northern corner of the building. The central feature of the building, which remains a focus for Anzac Day commemorations, is the constantly lit vestibule containing the Book of Remembrance, visible from a variety of vantage points. Incorporating a large hall, function room and a concert chamber, the building is used for concerts, as a conference facility and for other public events.

The War Memorial Hall has always been widely acknowledged by architectural historians as a landmark in New Zealand architecture for its Modernist design. In recognition of this achievement, it won the New Zealand Institute of Architects Gold Medal in 1961 and the Institute's 25-Year Award in 1998. It remains a focal point for the community, and a key building in Wanganui's Civic Centre. It has cultural and symbolic significance as the city's main war memorial.