Carthona is described by the Heritage Council as an "impressive two storey mansion with cellars, of mannerist Tudor Gothic style.

Built of sandstone, exterior there is a profusion of gabled slate roofs having castellated parapets and balconies dominated by tall tudor chimneys.

"[1] It was built in 1841 by Sir Thomas Mitchell and it is believed that many of the keystones of doors and windows were carved by him.

Soon after Mitchell moved into Carthona he set out on his fourth expedition in search of an overland route from Boree in NSW to the outpost named Victoria at Port Essington, in the present day Northern Territory.

[4] In 1847 Mitchell again went to England and it seems that, at least initially, he may have intended not to return as an advertisement in the Sydney Morning Herald in February 1847 lists for sale all of his property including Carthona.

Carthona is described as "the very splendid family mansion with spacious stabling and two acres of ground at Mrs Darling's Point, the present residence of Sir Thomas Mitchell, Surveyor-General.

In 1855, after his return to Sydney while conducting surveying work in Southern New South Wales he contracted a chill and developed pneumonia.

[3]: 500  It seems that from about 1858 Carthona was rented by the Mitchell family to the Misses Cooksey as Blanche Mitchell, the youngest daughter mentions in her Diary on 17 July 1858 that Miss Cooksey called at Craigend Terrace where they were then living and paid her mother a quarterly rent.

Blanche Mitchell disliked the new accommodation and reminisced about her previous life at Carthona in her diary.

[12] and several years later the two remaining Cooksey sisters Catherine and Sarah also immigrated, and ran a boarding school for young ladies at Carthona from 1858 to 1872.

They then rented a house at 4 Grey Street, East Melbourne, where they lived until 1885, when Catherine died.

[18] After the Cooksey sisters left, Carthona was rented for some time by Mrs Tait who also ran a boarding school.

He was the son of George Allen (1800–1877) who was a prominent Sydney solicitor and owned Toxteth Park, Glebe.

[24] Carthona was put on the market in 1886[25] and was bought by James Sutherland Mitchell who at that time owned Etham, an adjoining property.

His father was James Sutherland Mitchell and his mother was Elizabeth Carter Laidley who died in 1868.

James was a partner in Tooths Brewery and William was employed by his father’s firm as a Manager.

[32] During the Boer War which is when Chipman resided at Carthona, he is reported to have organised a subscription fund to assist citizen soldiers who became known as the "Bushmen’s Contingent".

In 1892 Rickards made Sydney his headquarters and concentrated his efforts on owning or leasing theatres in the capital cities of Australia.

He went overseas annually to find suitable artists to bring to Australia and he is reported to have paid them generously.

[34] The Rickards lived at Carthona for two years while Harry continued to establish his theatrical business.

In 1904 he purchased the nearby property called Lansdowne which now forms part of McKell Park.

He substantially demolished this building and built a large Federation style house which he called Canonbury.

[47] In the mid 1950s Bushell purchased the waterfront gardens of the neighbouring Edgewater, 3-5 Sutherland Crescent, from Oliver Triggs.