Abstract: A process and system for recovering hydrocarbonaceous products from in situ oil shale formations. A hole is drilled in the oil shale formation and a processing gas inlet conduit is positioned within the hole. A processing gas is pressurized, heated, and introduced through the processing gas inlet conduit and into the hole. The processing gas creates a nonburning thermal energy front within the oil shale formation so as to convert kerogen in the oil shale to hydrocarbonaceous products. The products are withdrawn with the processing gas through an effluent gas conduit positioned around the opening of the hole, and are then transferred to a condenser wherein a liquid fraction of the products is formed and separated from a gaseous fraction.