Complex sentence: Western Culinary Institute's facility is located in downtown Portland, in the historic Galleria Building, the former Olds, Wortman & King department store, which is listed on the National Register of Historic Places.
Split into simpler sentences: Western Culinary Institute's facility is located in downtown Portland, in the historic Galleria Building. The building, formerly the Olds, Wortman & King department store, is listed on the National Register of Historic Places.