Interesting oddities about Lake Washington:
- Lake level dropped nine feet when the Montlake Cut was created in 1916, connecting it to Lake Union.
- Contains an island city, Mercer Island.
- Has three floating bridges, one of which, the Evergreen Point Floating Bridge, is the longest in the United States.
- Is the site of a drowned forest which is evidence of a magnitude 9 earthquake in Washington in the year 1700. Although no Westerners were in the Northwest to keep records, the earthquake's exact date and time is known because of the tsunami it generated coming ashore in Japan.
- A World War II era F4U fighter plane was ditched into the lake in 1950 near Sand Point Naval Station. Thirty-three years later, the well preserved plane was pulled from the lake, restored and is now on display at the Museum of Flight in Seattle.
- Concern over pollution of Lake Washington due to untreated sewage led to the creation of the Seattle Metropolitan District ("Metro") in the late 1950s.