It originally housed the factory for making Erector Set toys, invented by Alfred Carlton Gilbert. The last official sets were produced there in 1967, after the company went out of business in that year. The Gilbert Co. assets were purchased by Gabriel Toys and moved to Lancaster, Pennsylvania.
In recent years, Erector Square has been turned into a home for various artists, researchers, and yoga and pilates studios, as well as one of the many locations for the yearly City-Wide Open Studios, run by Artspace, a non-profit arts organization. It is part of the revitalization of the greater New Haven area.
- "A History of Type III Erector - Girders & Gears". www.girdersandgears.com. Retrieved 13 April 2019.