A process is disclosed for converting Tar Sand to fuels and/or valuable chemicais. The process comprises the steps of a) activating Tar Sand to make it more susceptible to conversion; c) partially converting the Tar Sand to a solubilized material; and d) subjecting the unconverted Tar Sand to a second conversion step. The process optionally comprises a step b) of adding a solvent to the activated Tar Sand. In a preferred embodiment the solubilized Tar Sand obtained in step c) is removed before the unconverted Tar Sand is subjected to step d).