Castlecrag is a suburb of historical significance that is bounded to the north, east and south by Middle Harbour and to the west by Eastern Valley Way.

[5] Many early homes in Castlecrag were built using natural stone to blend into the environment, a common practice in architecture of the Arts and Crafts Movement, which was concerned with creating "the human touch" as distinct from mass production.

[17] The pair believed this could be achieved by encouraging social interaction, providing opportunities for people to contribute to their community and planning many parks and recreational spaces.

[17] The Griffins lived in Castlecrag from 1925, and actively participated in the community, planting native trees, landscaping and developing a natural amphitheatre.

[18] Marion Mahony Griffin had a passionate interest in the arts and helped instigate the creation of the Haven Scenic Amphitheatre where plays and festivals were held.

[11] The architects designed reserves that were linked together by a network of walkways, providing the community with ample space for recreation and bushwalking whilst retaining the bushland backdrop.

[14] The Griffin's plan involved 20% of the land at Castlecrag being set aside for parkland - considerably more than the amount dictated by Council regulations, 2%.

[24] The Griffins promoted respect for the natural environment by planting and protecting native trees in both public reserves and gardens and by establishing covenants on the land.

[27] The covenants also required residents to pay a levy that supported the ongoing maintenance of reserves, tree planting and other activities designed to safeguard the natural environment.

[28] Today, the national, state and local governments as well as heritage organisations acknowledge the importance of protecting the built and natural environment at Castlecrag and have established controls over its management and development.

[31] The Griffins' designs boasted innovations such as the kitchens' pass-through pantries and twin sinks, the close-to ground floor levels and the picture window.

[32] Some aspects of the Griffins' houses in Castlecrag were unusual and unconventional such as the treatment of stonework, the window details and the flat roofs.

[25] This, in addition to many of the houses being single story and boasting colours of the natural surroundings exemplifies the Griffins' objective which did not involve establishing imposing and artificial built structures, but rather to have the buildings blend in with the environment; retaining the bush setting.

More than half of its households enjoy incomes that are within the top quartile of Sydney, but there are exceptions[44] reflected in the median house price.