thumb|280px|[[Lake Quinault]]
Grays Harbor County is a county in the U.S. state of Washington. As of the 2020 census, the population was 75,636. Its county seat is Montesano, and its largest city is Aberdeen. Grays Harbor County is included in the Aberdeen Micropolitan Statistical Area.
History
The area that comprises modern-day Grays Harbor County is the ancestral territory of several indigenous Coast Salish peoples, including the Quinault and Lower Chehalis. They first came into contact with European explorers in the late 18th century and the tribes were later afflicted by regional epidemics. Grays Harbor was named for Boston fur trader and merchantman Robert Gray, who entered the bay on May 7, 1792. It was originally named Bullfinch Harbor and later Chehalis Bay before it was renamed for Gray. The first permanent white resident in the future county was William O'Leary, an Irish immigrant who settled on the south side of Grays Harbor in 1848.
The modern-day Washington Coast was originally part of the Oregon Country, which was administratively shared between the United States and British North America until the signing of the Oregon Treaty in 1846, which ceded it to the United States. The American Provisional Government of Oregon, which had been established prior to the treaty, created Lewis County on December 21, 1845. It encompassed most of the territory north of the Columbia River and west of the Cascade Mountains. The area around Grays Harbor remained part of Lewis County as it was transferred into the reorganized Oregon Territory in 1848 and later Washington Territory, created in 1853. The first county seat was at Bruceport on Willapa Bay until a referendum in 1860 moved it to the homestead of the Scammon family in modern-day Montesano.
Geography
According to the United States Census Bureau, the county has a total area of , of which is land and (14%) is water.
Due to the flat topography of the county and the drainage of the Chehalis River watershed into the Pacific Ocean, the region experiences repeated floods. In addition to tidal surges and coastal flooding, high waters stemming from excessive rainfall events are often difficult to shed. , the value of various buildings and infrastructure in flood risk areas within the county is valued at over $1.0 billion.
Geographic features
- Aberdeen Lake
- Chehalis River
- Duck Lake
- Failor Lake
- Grays Harbor
- Humptulips River
- Hoquiam River
- Lake Quinault
- Olympic Mountains
- Olympic Peninsula
- Pacific Ocean
- Quinault River
- Quinault Rain Forest
- Satsop River
- Wishkah River
- Wynoochee Lake
- Wynoochee River
State parks
- Griffiths-Priday State Park
- Lake Sylvia State Park
- Ocean City State Park
- Pacific Beach State Park
- Twin Harbors State Park
- Westhaven State Park (now part of Westport Light State Park)
- Westport Light State Park
Major highways
- 20px State Route 8
- 20px U.S. Route 12
- 23px U.S. Route 101
- State Route 105
- State Route 107
- State Route 109
Adjacent counties
- Jefferson County – north
- Mason County – northeast
- Thurston County – east/southeast
- Lewis County – south/southeast
- Pacific County – south
National protected areas
- Chehalis Indian Reservation
- Colonel Bob Wilderness
- Copalis National Wildlife Refuge
- Grays Harbor National Wildlife Refuge
- Olympic National Forest (part)
- Olympic National Park (part)
- Quinault Indian Reservation