Ironically, not a single scrap of land is actually antipodal to Australia. This is pretty surprising, considering how big Australia is; it is as if a cylindrical core of the Earth had been pushed downunderward, leaving a depression in the North Atlantic Ocean and a rise constituting Australia. Bermuda is almost antipodal, but it actually fits into the bay at Perth.
The United States similarly represents a core that has been pushed upoverward; the only land antipodal to it is a small slice of Kerguelen Island, glacial and uninhabited, which is antipodal to part of Rhode Island (which is not an island). Hawaii is an exception.