The hotel is heritage listed and is notable for its unusual mix of architectural styles, including Art Deco and Edwardian.

[1] The Australian retailer Mark Foy began to purchase the site in 1902 for the purposes of a hydropathic sanatorium under the belief that the land contained mineral springs.

Hargraves, registrar in Equity and a trustee of the Australian Museum in Sydney, son of the man who claimed credit for the discovery of gold in New South Wales in 1851.

The single-storey house, with elaborate tree and shrub plantings, was bought by Mark Foy in 1901 and developed into the Hargravia section of the Hydro.

[4] It is not known if he requested the name change to make it sound more prestigious, or if he wanted to avoid confusion with another town called Medlow, also in New South Wales.

Foy spared no expense, building gardens, bringing in his own herd of cows for milk, and not a man to be bested, is said to have had electricity and a working telephone four days before metropolitan Sydney.

After travelling in these containers from Germany to Australia the water reportedly tasted awful, and so it was assumed that it must have been good for a person's health.

In October 1913, it was reported that Foy had sold the property to businessman and NSW parliamentarian James Joynton Smith for a reputed £60,600.

The casino building is an ornate late Victorian Italianate wedding-cake structure which serves as the grand ballroom of the current establishment.

The casino will re-open as the main guest entry to the hotel complex with Lounge and Function Space, Pre-function to Wintergarden and linked to the new Passage bar.

As well as Dame Nellie Melba and Dame Clara Butt, other famous guests of the hotel have included: munitions heiress Bertha Krupp, who donated a Bechstein grand piano to the hotel; Sir Arthur Conan Doyle, author of Sherlock Holmes, for whom the Blue Mountains were the inspiration for The Lost World; and more recently, Russell Crowe who was asked to remove his baseball cap while dining in the Great Dining Hall in 1994.

[citation needed] Boxer Tommy Burns set up a training camp at the Hydro Majestic ahead of his world title fight against Jack Johnson in Sydney in 1908, running for miles on mountain tracks in preparation.

[15] Australia's first Prime Minister, Sir Edmund Barton died of a heart attack at the hotel while holidaying there in 1920.