Half of Cottage Lake’s homes were built after 1984
More historic than 11% of U.S. towns · #223 of 285 in Washington. What drives it
Most of Cottage Lake was built recently: 2% of its homes predate 1940 and the median home dates from 1984. Below: 5 old photos and papers, maps from 1950 on, and the census since 2000.
On its age, its old homes and the National Register, Cottage Lake is more historic than 11% of U.S. towns, #223 of 285 in Washington. Its National Register listings hold the grade up; its share of homes from before 1940 pulls it down.
D
HistoryA character grade: shown, never part of Cottage Lake’s overall grade.
Few Washington towns list much on the Register (a typical Washington town has 0.1 per 10,000 residents, the U.S. 2.4), so Cottage Lake’s 0.0 sits below most of its state (27% of Washington towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
How sure. Graded on two of the three inputs, so a change in either one moves the letter more than it would with three. The pre-1940 share (±1.1 points) is firm at this size.
Founding year: our sources. Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
The story so far
Cottage Lake, in brief
Wikipedia doesn’t have a history of Cottage Lake yet. The photos, dates and memories neighbors add here are how it gets written.
Cottage Lake is a census-designated place (CDP) in King County, Washington, United States. The population was 22,857 at the 2020 census. The lake itself falls within the 98072 ZIP code, while the developments east of the lake fall under the 98077 ZIP code. The census designated area is also split between the Northshore school district and the Lake Washington school district. Based on per capita income, Cottage Lake ranks 13th of 522 areas in the state of Washington to be ranked. Coldwell Banker ranked Cottage Lake #1 in 2013 for the fastest growing suburb in America.
Its population held steady between the last two censuses: 22,494 in 2010, 22,857 in 2020.
Intro from Wikipedia. Population: U.S. Census Bureau.
Timeline
Cottage Lake, 1909 to 1964
Woven from the archive, old maps, post office records, the National Register and the people born here.
Nothing in the archives for these yearsWeddings on Main Street, storms, parades, school pictures, the old store. If it’s in your family album, it belongs here.
Nothing in the archives for these yearsWeddings on Main Street, storms, parades, school pictures, the old store. If it’s in your family album, it belongs here.
Cottage Lake is more historic than 11% of U.S. towns, #223 of 285 in Washington. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
How old are the homes in Cottage Lake?
2% of Cottage Lake’s homes were built before 1940 (Census estimate, ±1.1 points), against a typical 4.3% for a Washington town; the median home was built in 1984.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From Wikimedia Commons (6), U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the US Post Offices dataset (Blevins & Helbock) and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
1964
1964
1964
2004
