Pine Grove is located in northwestern Ferry County and is east of
Republic, the
county seat. The Pine Grove community rests immediately south of the intersection of State Routes
20 and
21. Route 20 leads east across Sherman Pass to
Kettle Falls, while Route 21 leads north to
Curlew and to the
Canadian border. According to the
U.S. Census Bureau, the Pine Grove CDP has a total area of , all of it land. It is in the valley of the
Sanpoil River, a south-flowing tributary of the
Columbia River. ==References==