Nearly $60 million worth of real estate in one of Toorak's most-exclusive streets has been reduced to a patch of dirt, with mystery surrounding what's going to happen to it.

On well-heeled St Georges Road, where two grand mansions once stood side by side, sits a couple of Melbourne's priciest vacant blocks after bulldozers razed both properties.

Melbourne real estate records were smashed a few years ago when a Chinese buyer paid just under $40 million for the 1920s Mowbray mansion at 18 St Georges Road.

The gates of Mowbray remain after a 1930s mansion was knocked down in Toorak. Credit:Luis Enrique Ascui

The palatial six-bedder, sitting on 5000sqm with a swimming pool and tennis court, succumbed to the dozer blade in recent months after it was damaged by fire and vandals started getting inside the vacant property.