Jared Campbell's WURL page describes it like this: "The Wasatch Ultimate Ridge Linkup or “WURL” is an incredible ridge route circumnavigating Little Cottonwood Canyon in the Wasatch Mountains of Utah. The route mainly consists of scrambling, boulder hopping, and a few rugged trails. It is ~36 miles long with ~18kft of elevation gain." Campbell's site gives much more information and a list of completions.
Map from Jared Campbell