The University of Illinois’ Oak Street High Density Storage Facility holds over four million items — four million! That’s a lot of archival material (including maps, film, books, and more). It’s all kept at a cool 50 degree Fahrenheit, and a delightfully crisp 30% humidity. It’s basically my ideal winter climate.
You can read more about the facility in this 2019 Illinois News Bureau article, and on the U of I website.
Here’s a video of the shelving being installed.
Top image by Fred Zwicky.