Driving to Whitman Mission National Historic Site From Walla Walla, WA: Take So. 2nd Street to US-12W Merge onto US-12W via the ramp on the left Drive 5.89 miles to the Whitman Mission NHS sign Turn left onto Spalding Road for .19 mile then right on Old Highway 12 for 0.8 mile Go left on Swegle Road for 0.5 mile Turn left on Whitman Mission Road Road ends in circular parking area in front of the Visitor Center