Willoughby is a city in Lake County, Ohio, United States, along the Chagrin River.

In 1835, the village was permanently named "Willoughby" in honor of Westel Willoughby, Jr., a public health official that the founders of a short-lived Medical College, which was based in the city, hoped to attract to the area.

[7] Many historical buildings from this period survive to this date, affording the downtown Willoughby area some outstanding specimens of 19th century architecture.

In World War I, the U.S. Army chose Willoughby as the site for a chemical weapons plant producing lewisite.

Several memorials and historical relics are displayed in Wes Point Park, the center of downtown Willoughby, to honor those that have served.

Willoughby is the only town in America that has belonged, at one time or other, to six counties (Washington, Jefferson, Trumbull, Geauga, Cuyahoga, and Lake).

To the west is Cleveland, allowing for access to big businesses and a high neighboring population density.

It also has access to Mentor Ave, a long stretch of mostly commercial buildings spanning alongside the coast of Lake Erie.

[5] 19.0% were of German, 15.8% Italian, 13.3% Irish, 8.2% English, 5.6% Polish, 5.6% American and 5.4% Slovene ancestry according to Census 2000.

It then housed the Willoughby-Eastlake Technical Center, located in downtown Willoughby.

The demolition of the old Willoughby Middle, Longfellow Elementary, and North High School began and ended Summer 2019.

[19] The Andrews Osborne Academy, a private boarding school, is also located in Willoughby.