In its heyday, Alcatraz Island housed more than 260 prisoners, with notorious gangsters such as Al Capone, George "Machine Gun" Kelly and James "Whitey" Bulger serving time on the rocky outpost.

President Donald Trump says he wants Alcatraz to be returned to use as a maximum-security prison. Here's what to know about the infamous prison.

President Donald Trump on Sunday said that he would order the government rebuild and reopen Alcatraz, a former prison on a small island of the same name off the coast of San Francisco that once housed some of the most dangerous criminals in the country,