FCI Sandstone, in Sandstone, Minnesota, has one of the more winding histories among federal prisons. It was established in 1939, opening when a group of selected inmates was transferred there from the U.S. Penitentiary at Leavenworth in Kansas to help populate the new institution. Its population stayed modest through the 1940s, hovering around 350 or so, and by the end of that decade the numbers had dropped enough that the Bureau of Prisons actually closed it as a prison and repurposed the site as a mental health hospital, a use it served from 1949 until 1959. After that decade-long detour, it was converted back into a federal prison and has operated in that role ever since. Today it's classified as a low-security facility for male offenders and sits in a fairly remote part of east-central Minnesota, roughly 100 miles northeast of the Twin Cities and about 70 miles from Duluth. For families, the remote location is worth planning around, since it's a couple hours' drive from the nearest major metro area, but the facility itself has a longer and more unusual institutional history than many of its more straightforward federal counterparts.