Commander George Vancouver guaranteed In 1791, the southern piece of Western Australia for the British Crown. As he investigated along the drift, he found one of the world's finest regular harbors and named it the Princess Royal Harbor and King George III Sound. Amid the nineteenth century, the loss of this key port to a foe maritime squadron was perceived as a potential risk to the security of Australia. Thus – before Federation - all the Australian states consented to relatively pay for the development of a post with the Imperial British Government providing the weapons. The Fort was opened in 1893 as the principal government guard of Australia, and today is known as the Princess Royal Fortress.