The heritage of Ku-ring-gai comprises a rare blend of fine domestic architecture within a landscape of indigenous forests and exotic plantings and gardens.
Ku-ring-gai as a whole is of national and state heritage significance because of:
- The outstanding quantity, quality, depth and range of its twentieth century architecture. It contains houses designed by many of Australia's prominent twentieth century architects who have influenced the mainstream of Australian domestic architecture nationally; including John Sulman, Howard Joseland, Hardy Wilson, Leslie Wilkinson and Harry Seidler.
- The evidence it provides of twentieth century town planning and conservation philosophies - the segregation of residential areas from other urban uses, subdivision patterns which reflect a range of suburban aspirations, the use of residential district proclamations to create and retain domestic environmental amenity, street tree planting and post-war neighbourhood planning.
- The railway whose presence demonstrates the bargaining power of public works and services in gaining votes for federation.
Ku-ring-gai is of regional significance for:
- The evidence it retains in its surrounding national parks, along its creek lines and in its public and private gardens, remnants of the original Blackbutt and Blue Gum forests and associated woodlands, understoreys and dependent fauna - a resource of wide ranging scientific research potential.
- Its coherent aesthetic values resulting from a combination of elevated locations, good soil, large trees, extended views, fine architecture and established gardens inspiring artists such as Grace Cossington Smith and Lionel Lindsay, visionaries such as John Sulman and J.J.C Bradfield and writers such as Ethel Turner honour Ku-ring-gai with their works.
- For the technical and design innovation in its buildings and gardens - demonstrating some of the earliest examples of Australia's first school of architecture at Sydney University, some of the earliest use of cavity walls, Marseilles tiles and innovative landscape designs of renowned exponents such as Edna Wallings, Paul Sorensen and Jocelyn Brown.
Ku-ring-gai is also of heritage significance for:
- The evidence provided by its rich history and all its sequential layers - from very early timbergetting, the long period of relative isolation from built suburbia, orchards and farming followed by the rapid growth of suburban development in response to elevated topography, 'clean air' and the establishment of the railway.
- The evidence offered by its built landscape and garden design incorporating a variety of horticultural styles and in harmony with the natural landscape such as those at Swain Gardens, Bobbin Head, large private estates and the gardens at railway stations and well-designed gardens of cultivated botanical specimens such as Eryldene and the Ku-ring-gai Wildflower Garden.