Located entirely within the Seattle city limits, the fresh-water Lake Union covers 580 acres and has an average depth of 34 feet. The convenient location makes it a popular destination for kayaking, recreational boating, and seaplanes. Seaplanes are surprisingly common because both Kenmore Air and Seattle Seaplanes have seaplane bases on Lake Union.
There are many places of interest to see via kayak around Lake Union, from Gas Works Park and multiple bridges to hundreds of floating homes—including the one featured in the film Sleepless in Seattle. Paddle east of Lake Union to reach Portage Bay, the Montlake Cut, and Union Bay beyond. Paddle west from Lake Union to reach Puget Sound via the canal system.
Lake Union is named for Seattle pioneer Thomas Mercer's famous prediction in the mid-1800s that Lake Washington would one day connect to Puget Sound through a canal system, which is the case today.