Given the following context:

Within a year of the enquiry, almost 100 cells had been enlarged by knocking down the inner wall between two cells, and a classification system was introduced. Internal walls were constructed in the main block, creating four separate divisions. Following the urgings of the prison Superintendent George and various official enquiries, new workshops were built to provide increased useful employment for prisoners. Five spaces were designed for tailors, bookbinders, shoemakers, mat makers and painters.New regulations for prison officers were published in the Government Gazette in 1902, and a new Prisons Act was passed in 1903. While in theory the passing of the Act should have resulted in significant prison reform, this did not eventuate. The legislation left much of the changes to executive regulation, at the discretion of the governor, and was described by the media as a feeble document.New Division, completed in 1907 and occupied in 1908, resulted from the 1899 Commissioners' report recommending a modified version of the separate system. The new division was similar in design to Henderson's 1850s structure, but was constructed in an L-shape, was only three stories tall, and had electric lighting. It also differed in its use from the main cell block.  Unlike occupants of the earlier building, prisoners remained continuously in their cells except when exercising in separate yards, watched panopticon-style by a warder in a central tower.
In 1911 another Royal Commission investigation into Fremantle Prison recommended closing the facility. Its report was ignored by the state government, which was more concerned with building infrastructure such as roads and schools than the plight of its prisoners. However, there was a rapid change in prison policy, with the appointment of a superintendent, Hugh Hann, who had recent English and colonial experience, and the election of a Labor government with members interested in penal reform. One immediate result was the dismantling of the separate system at Fremantle Prison and...

answer the following question:

What was one of more than 50 military prisons across Australia holding a combined total of more than 12,000 enemy aliens and prisoners of war? 

Fremantle Prison