The urban renewal and the rehab of the Marcus Whitman Hotel began about 20 years ago.  Whitman is the premier private college of the Northwest,  having a nuclear reactor for its physics dept.  and very very good at music, language,  as a liberal arts school must be. 

 Walla Walla was the residential town for Palouse wheat  ranch millionaires and merchants of a century ago.  Many,  many restored large homes from before the Great Depression.  Wide streets with stately trees.  The prison is on the "other side of the tracks" so to speak.  At one time WW  had a fabulous Italian restaurant that you had to access through a bar that was more dive than salon.  Most of downtown was far into urban renewal two decades ago.  There are two towns in the PNW I love to drive around in neighborhoods to see old homes:  Walla Walla and Helena,  MT.  Pre WWI fortunes were many. 

Walla Walla is about as old as any town in Washington state,  as the references to Marcus Whitman,  the missionary,  abound.