King County, Washington facts for kids

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King County

U.S. county

Flag

Logo

Location within the U.S. state of Washington

Washington's location within the U.S.

Country

United States

State

Washington

Founded

December 22, 1852

Area

• Total

2,307 sq mi (5,980 km²)

• Land

2,116 sq mi (5,480 km²)

• Water

191 sq mi (490 km²)

Population

(2020)

• Total

2,269,675

• Estimate

(2025)

2,344,939

• Density

983.82/sq mi (379.86/km²)

Congressional districts

1st, 7th, 8th, 9th

King County is an exciting and busy county located in the U.S. state of Washington. It is the most populous county in Washington, meaning more people live here than anywhere else in the state. According to the 2020 census, over 2.2 million people lived in King County. That makes it the 13th-most populous county in the whole country. The county seat is Seattle, which is also the state's most populous city.

King County has towering mountains, quiet islands, huge lakes, and bustling cities filled with big ideas. It is part of the larger Seattle metropolitan area, along with Snohomish County to the north and Pierce County to the south. Many people live in Seattle's suburbs, which were once quiet bedroom communities where people only slept at night. Today, these vibrant communities are major centers for the modern technology industry.

The History and Naming of King County

Long before cities existed here, several Native American groups known as the Coast Salish lived across this land. The Duwamish people built villages around the shores and rivers where Seattle sits today. Farther east, near the foothills, lived the Snoqualmie Indian Tribe. The areas around the Green River and the White River were home to the Muckleshoot people. Native families hunted, gathered berries, and caught salmon in the sparkling rivers for many generations.

In the autumn of 1851, a group of American pioneers called the Denny Party arrived at Alki Point. During that cold first winter, more than a thousand Native Americans shared the land with a few dozen settlers. The local tribes helped the newcomers survive by showing them how to gather food, build shelters, and navigate waterways.

On December 22, 1852, lawmakers in the Oregon Territory created the county out of land from Thurston County. They named it after Alabamian politician William R. King, who had just won election as the Vice President of the United States under President Franklin Pierce. On January 11, 1853, leaders chose Seattle to be the official county seat. Soon after, the land became part of the newly organized Washington Territory.

In the beginning, King County was even larger and stretched all the way across the water to the Olympic Peninsula. A pioneer doctor named Doc Maynard helped rearrange local borders, which created nearby Kitsap County. In 1853, prospectors discovered Coal near the Black River. Soon, workers opened mines around Lake Washington, and the Seattle and Walla Walla Railroad began carrying fuel from fields in Renton and Newcastle.

Renaming the County for a Civil Rights Hero

The former county flag used an imperial crown symbol until 2007.

Originally, the county was named after politician William R. King. However, leaders later decided to change who the county represents. In 1986, the King County Council voted to rename the county after Martin Luther King Jr.. He was a famous minister and leader in the American civil rights movement who taught equality and kindness. The council explained that the original namesake had supported enslaving people, which did not reflect the values of the community.

Governor Christine Gregoire officially signed this change into state law in 2005. The county kept the name "King County," but its namesake became the famous civil rights leader instead. In 2006, county leaders voted to replace their old imperial crown logo with an image of Martin Luther King Jr. The new official logo and flag design was proudly revealed to the public in 2007. Dr. King had actually visited Seattle in November 1961, when his friend Reverend Samuel B. McKinney invited him to speak at local churches.

Discovering the Geography and Natural Wonders

King County stretches from Puget Sound to the Cascade Mountains.

King County covers a big piece of land and water in the Pacific Northwest. According to the United States Census Bureau, the county covers an area of 2,307 square miles (5,980 km²). Land takes up 2,116 square miles (5,480 km²), while rivers, lakes, and bays cover 191 square miles (490 km²). King County is nearly twice the size of the entire state of Rhode Island.

The county has very diverse borders. It touches Snohomish County to the north and Pierce County to the south. To the east, across the high mountains, lie Chelan County and Kittitas County. To the west, across the salty water of Puget Sound, lies Kitsap County. The county also includes large islands out in the sound, such as Vashon Island and Maury Island.

Mountain Ranges and Mighty Peaks

Granite Mountain rises high in the eastern Cascade Range.

The landscape rises sharply as you travel from west to east. The western part borders the sea, but the eastern portion rises into the rugged Cascade Range. The tallest point in the county is Mount Daniel, which reaches 7,959 feet (2,426 m) into the sky.

Hiking trails wind through smaller peaks known as the Issaquah Alps, where families love to explore nature. Another famous hiking spot is Mount Si, a huge rocky peak that towers over the forest floor. Much of the wild eastern forest belongs to the Mount Baker-Snoqualmie National Forest, where giant evergreen trees provide shelter for wildlife. King County also contains islands inside lakes, including the busy community of Mercer Island, and human-made islands like Harbor Island near the city port.

Lakes, Rivers, and Waterways

Water is everywhere in King County. The region has 760 lakes and about 3,000 miles (4,800 km) of flowing streams and rivers. One of the most famous sights is Snoqualmie Falls, a massive waterfall that plunges over a tall cliff.

Important rivers flow down from snowy mountain peaks toward the ocean:

The Cedar River supplies fresh drinking water to hundreds of thousands of people.
The Green and Duwamish River system winds through farmlands and industrial zones into Elliott Bay.
The Snoqualmie River flows through valleys where local farmers grow delicious vegetables.
The White River carries cold glacier meltwater from the giant volcanoes to the south.
Other important mountain streams include the Skykomish River, Tolt River, Taylor River, and the rushing Raging River.

King County also boasts huge bodies of fresh water, such as Lake Washington and Lake Sammamish. Closer to downtown Seattle sits Lake Union, where houseboats float and seaplanes take off directly from the water. Another large lake, Lake Youngs, stores clean tap water behind protected forest boundaries.

Caring for the Environment

Because King County has so much water, local communities pay close attention to climate change. Warmer temperatures can cause heavy winter rains that lead to river flooding. In the mountains, warmer winters mean less snow builds up, which reduces summer water supplies. The county government works hard to protect salmon streams, clean up coastal waters, and cut greenhouse gas emissions to keep the planet healthy.

Getting Around: Transportation Networks

Moving millions of people requires lots of teamwork and clever transportation systems. Several major freeways cross through the county to connect towns and shipping hubs:

Interstate 5 runs north and south through the heart of Seattle.
Interstate 90 heads east over floating bridges across Lake Washington and through the mountains.
Interstate 405 carries traffic around the eastern side of Lake Washington.
U.S. Route 2, also called the Cascade Highway, winds through the far northeastern corner along the Skykomish River.
Other busy highways include State Route 18, State Route 99, State Route 167, State Route 520, and State Route 522.

Public Transit by Bus, Rail, and Boat

King County offers many choices for riding public transit. A major agency called King County Metro runs hundreds of buses, specialized vanpool rides, and paratransit services for people who need extra mobility assistance. Metro also operates quiet electric trolleybuses powered by overhead wires and the modern Seattle Streetcar tracks.

Another regional transit agency, Sound Transit, operates the high-speed Link light rail trains and the large Sounder commuter rail trains that connect people across county lines. Express commuter buses from Pierce Transit and Community Transit also bring travelers into the area. Most riders pay their fares with a handy electronic smart pass known as an ORCA card.

Because Puget Sound separates local towns, ferries play a huge role in daily travel. The state-run Washington State Ferries system operates giant auto-ferries out of Colman Dock in Seattle, carrying passengers toward Bainbridge Island and Bremerton. Ferries also connect Fauntleroy in West Seattle with Vashon Island and Southworth. King County also runs its own passenger-only King County Water Taxi boats, while Kitsap Transit runs fast boats known as Kitsap Fast Ferries across the sound.

The People of King County: Demographics

Historical population
Census	Pop.	%±
1860	302	—
1870	2,120	602.0%
1880	6,910	225.9%
1890	63,989	826.0%
1900	110,053	72.0%
1910	284,638	158.6%
1920	389,273	36.8%
1930	463,517	19.1%
1940	504,980	8.9%
1950	732,992	45.2%
1960	935,014	27.6%
1970	1,156,633	23.7%
1980	1,269,749	9.8%
1990	1,507,319	18.7%
2000	1,737,034	15.2%
2010	1,931,249	11.2%
2020	2,269,675	17.5%
2025 (est.)	2,344,939	21.4%
U.S. Decennial Census

King County has grown tremendously over the past century. In 1860, only 302 non-Native settlers were counted in the county. Today, the population is well over 2 million residents. The center of population for the entire state of Washington is located in the eastern foothills of the county. King County's own balance point of population sits right on Mercer Island.

The county is home to families from all backgrounds and cultures. According to official census counts, about 54% of residents identify as White, nearly 20% identify as Asian, almost 11% identify as Hispanic or Latino, about 6.5% identify as Black or African American, and almost 7% identify with two or more races. Smaller percentages of people identify as Pacific Islander and Native American. Many people have family heritages tracing back to Germany, England, Ireland, and Norway.

Native Tribal Communities

King County is proud to be home to two federally recognized Native American tribes. The Muckleshoot reservation sits southeast of Auburn and has thousands of tribal community members living there. The Snoqualmie Indian Tribe has ancestral lands throughout the Snoqualmie Valley. Both tribes protect cultural heritage, run local businesses, and work to protect local forests and salmon habitats.

Helping the Community

Because King County is a popular place to live, housing has become very expensive. As home prices climbed, many people found themselves without a regular place to sleep. King County works with partner agencies, including the King County Regional Homelessness Authority, to provide emergency beds in a homeless shelter or villages of cozy tiny house shelters. Charities, churches, and community volunteers help provide warm meals and support families who need shelter during freezing winter nights.

County Economy and Local Jobs

King County is the economic powerhouse of Washington. Many global corporations have their main headquarter buildings here. The region is famous for software, computer technology, aviation, and scientific research.

Major industries that employ workers throughout King County include:

Healthcare workers and hospital doctors who care for patients.
Scientists, engineers, and computer experts who design software.
Public workers who teach in schools and run government services.
Workers in food services and hotels who welcome visitors from around the world.
Manufacturing teams, such as Boeing, which builds large commercial airplanes.

How the County Government Operates

King County has a local government that looks after roads, public health, parks, voter registration, and transit systems. The executive leader is the King County Executive. Legal court cases are heard in the King County Superior Court and the district courts, which meet in the historic King County Courthouse in Seattle.

Public safety is supported by the King County Sheriff's Office. Law enforcement teams patrol unincorporated areas that sit outside normal city limits. The King County Council consists of nine elected council members who represent different districts and vote on county laws.

Voters also elect commissioners to run the Port of Seattle, which was created back in 1911. The Port operates giant waterfront piers for container ship cargo and luxury cruise ship docks. It also manages Fishermen's Terminal, which shelters North Pacific fishing boats, as well as public marina boat slips and the busy Sea-Tac International Airport.

Education and Learning for Kids

King County places a huge emphasis on education and reading. Children attend school across many excellent school districts.

Public School Districts

Local school districts include:

Seattle Public Schools (the largest district in the state)
Bellevue School District
Lake Washington School District
Kent School District
Federal Way Public Schools
Highline School District
Renton School District
Northshore School District
Auburn School District
Issaquah School District
Shoreline School District
Snoqualmie Valley School District
Tahoma School District
Riverview School District
Enumclaw School District
Mercer Island School District
Tukwila School District
Vashon Island School District
Skykomish School District
Fife Public Schools

Wonderful Public Libraries

King County has some of the best library systems in the United States. The King County Library System operates nearly 50 community libraries packed with books, digital media, and homework clubs. Meanwhile, the city of Seattle is served by the famous Seattle Public Library, which has 27 branches, including a striking glass central library downtown.

Cities and Towns in King County

King County is made up of many exciting cities, historic towns, and scenic rural communities.

Major Cities

Some of the county's incorporated cities include:

Seattle – the county seat and largest city
Bellevue – a major business and tech center
Kent – a hub for manufacturing and warehousing
Renton – home to airplane assembly and Lake Washington parks
Federal Way – located in the southern part of the county
Kirkland – known for lovely waterfront parks along Lake Washington
Redmond – famous as a major global computer software capital
Auburn – an active rail and shopping community
Burien – a seaside community near Puget Sound
Sammamish – a scenic city surrounded by lakes and green hills
Shoreline – located just north of Seattle
Bothell – a growing city along the river
Issaquah – nestled at the base of tall foothills

Charming Towns and Island Communities

Smaller towns offer historic charm and natural beauty:

Skykomish – a mountain town along the railroad
Snoqualmie – famous for its historic railroad museum and majestic waterfall
North Bend – a popular mountain base camp for hikers and explorers
Vashon – a peaceful island community reached only by ferry boat
Hunts Point and Yarrow Point – quiet lakeside towns on the eastern shore

From the sparkling waters of Puget Sound to the snowy peaks of the Cascade Mountains, King County is a unique and thriving home for millions of people.