Conquest Quadruples Yield on Historic Castlecrag Scheme

A Sydney suburb designed by the Burley Griffins is in line for an upscaled Housing Delivery Authority scheme as a two-tower proposal goes on exhibition at historic Castlecrag.

Edinburgh Group Developments is behind the 13-storey, $106-million project slated for 100 Edinburgh Road.

Its shareholders are Conquest chief executive Michael Akkawi and chief operating officer Glenda Lam.

An approval was granted in December 2024 by the Sydney North Planning Panel for a smaller scheme with a supermarket and 38 apartments, but the plans on show call for an additional seven storeys in the masterplanned model suburb to increase the yield to 150 homes.

Under the proposal, the four-storey podium would comprise two 11-storey residential towers above and five levels of basement car parking below. The apartments would include 10 affordable homes, and typologies across one to three bedrooms, duplexes and penthouses.

Retail tenancies in the FJC Studio design would include a supermarket, as well as restaurants and cafes and potentially medical offices, according to the proposal. Submissions to the earlier approval had particularly focused on the lack of dining options in the development.

The 5099sq m site is about 8km north of the Sydney CBD and 2.5km from the Artarmon train station. A two-storey retail centre, the Quadrangle, stood on the site for decades, but has been demolished in preparation for development.

▲ The suburb has not had a supermarket since the Quadrangle was demolished in mid-2025 in preparation for the development.

The site comes with a complicated history. Dr Stanley Quek of property group Greencliff acquired the Quadrangle in 2016 and progressed the original mixed-use proposal in association with Luxcon.

Conquest acquired the DA-approved site in May 2025 from Quek, in a $69-million deal that Akkawi said took just 48 hours to close. An estimated development cost of $106 million is attached to the latest proposal, although a total cost of $250 million had been floated by Conquest for the smaller 38-apartment version.

▲ The Griffins’ design principles for the suburb prioritised the preservation of bushland, and the subservience of the built environment to the natural.

The 263ha suburb of Castlecrag was acquired and subdivided by Walter Burley Griffin and Marion Mahony Griffin in the 1920s. Their design for the suburb laid out roads along natural contours, and emphasised local stonework in buildings to blend into the environment. Walter Burley Griffin’s patented Knitlock system of brickwork was also employed in some houses.

In April, private equity investor Conquest expanded beyond its Sydney base to pick up the Coconut Grove site at Airlie Beach, Queensland, in an off-market transaction.

Proposals are also under way for a 500-home, $900-million development at the site of the Cyprus Club in Sydney’s Stanmore, as well as a $250-million, 78-storey build-to-rent tower at Parramatta.