Most people have heard of the Manhattan Project, but a great many have probably never heard of Project Matterhorn. Started under the leadership of Lyman Spitzer at Princeton University in 1951, this was the code name given to a controlled thermonuclear research effort. With support from Princeton and the US Atomic Energy Commission, Spitzer began to outline the basic concept for creating the stellarator, which was a device for confining and heating ionized hydrogen gas to release fusion energy for the production of power. Recently, the Digital Collections group at Princeton digitized many of the primary documents associated with this project, and this site represents their fine efforts thus far. On the site, visitors can view the documents that described the proposed stellarator, and other documents which discuss how various particles and bodies might interact within this device.