Lake Union Lake

Urban freshwater lake in Seattle, connected by ship canal

In central Seattle, Lake Union supports a dense cluster of houseboats, seaplane activity and kayak traffic; visitors encounter waterfront cafes, maritime museums and short boat tours.

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Lake Union at a Glance#

Address: Lake Union, Seattle, WA, United States

Admission: Free

About Lake Union#

Lake Union is a freshwater lake in central Seattle, Washington, immediately north of the city’s downtown and surrounded by residential and commercial neighborhoods. It covers about 580 acres and is a focal point for urban boating and waterfront recreation.

The lake is notable for its concentration of floating homes and houseboats, active seaplane operations, and a high density of marinas and small craft rentals. Popular shoreline attractions include Gas Works Park and waterfront cultural institutions, and the lake hosts community boating events and sailing programs.

The waterway became more regionally connected after the Lake Washington Ship Canal and the Hiram M. Chittenden Locks opened in 1917, linking Lake Union and Lake Washington to Puget Sound and enabling larger-scale marine traffic and industrial development along the canal.

Geographically the lake sits within Seattle city limits, bordered by the South Lake Union, Eastlake, Westlake and Northlake neighborhoods, with downtown Seattle immediately to the south.

  • Size and uses: Relatively small urban lake of about 580 acres (approximately 2.3 square kilometers), popular for seaplanes, houseboats and shoreline parks.
  • Viewing spots: Best vantage points for lake activity and skyline views include Gas Works Park and the west-facing piers of South Lake Union.

What to See#

  • Gas Works Park: Converted industrial site turned public park on the lake’s north shore known for panoramic views of the lake and Seattle skyline; contains picnic areas and the preserved remains of a former coal gasification plant.
  • Museum of History & Industry (MOHAI): Museum focused on Seattle and Puget Sound history located on the lake’s south shore; houses regional collections and rotating exhibitions and moved to its South Lake Union building in 2012.
  • Center for Wooden Boats: Nonprofit educational center preserving and demonstrating wooden boats; operates a public boatyard and offers rentals and sailing instruction on the lake.
  • Hiram M. Chittenden (Ballard) Locks: Part of the Lake Washington Ship Canal system completed in 1917; the locks allow vessel passage between the lake system and Puget Sound and regulate water levels.

How to Get to Lake Union#

Central Seattle transit is best: the South Lake Union Streetcar and Link Light Rail (Westlake Station) connect to lakefront areas. Several waterfront parks provide pedestrian access: Gas Works Park (north shore) and South Lake Union Park (south shore) are prominent entry points.

Tips for Visiting Lake Union#

  • Travel to South Lake Union for the best mix of waterfront restaurants, museums and the Center for Wooden Boats.
  • Weekdays before 10am or after 6pm are the quietest times to stroll the waterfront; weekends are lively with paddleboards and seaplanes.
  • Rent a stand-up paddleboard or small electric boat if the weather is calm - it's the best way to see houseboats and floating gardens up close.

Best Time to Visit Lake Union#

Late spring through early autumn offers the best boating and waterfront weather; winters are wet but atmospheric.

Summer
June-August · 15-26°C (59-79°F)
Longest daylight and the most pleasant weather for boating and terraces.
Spring
April-May · 8-16°C (46-61°F)
Fewer tourists and cherry blossoms in the city; water is cool.
Autumn/Winter
October-March · 2-12°C (36-54°F)
Cloudier, rainier; the lake is quieter and seaplane traffic reduces.

Weather & Climate near Lake Union#

Climate

Lake Union's climate is classified as Warm-Summer Mediterranean - Warm-Summer Mediterranean climate with mild summers (peaking in August) and cold winters (coldest in December). Temperatures range from 2°C to 24°C. Moderate rainfall (948 mm/year).

Air Quality: AQI 30 Good
Temperature & Rainfall
Temperature Range
24°
Warmest Month
2°
Coldest Month
Monthly Conditions
Month Comfort Temp Feels Rain Sky Humidity Wind UV Daylight
January - 2° - 8° 2° 130 mm - - 3.3 m/s - -
February - 3° - 10° 4° 101 mm - - 3.3 m/s - -
March - 4° - 12° 6° 101 mm - - 3.4 m/s - -
April - 5° - 15° 10° 68 mm - - 3.4 m/s - -
May - 8° - 18° 13° 43 mm - - 3.3 m/s - -
June - 11° - 21° 16° 37 mm - - 3.4 m/s - -
July - 13° - 24° 18° 23 mm - - 3.3 m/s - -
August - 13° - 24° 19° 29 mm - - 3.1 m/s - -
September - 11° - 21° 16° 43 mm - - 2.8 m/s - -
October - 7° - 16° 11° 80 mm - - 2.8 m/s - -
November - 4° - 10° 5° 138 mm - - 3.3 m/s - -
December - 2° - 8° 2° 155 mm - - 3.3 m/s - -

Nearby Attractions to Lake Union#