The Chicago 80 Acre Map Library

is a catalog of individual pages, each representing 80 acres of land, based on the U.S. Department of the Interior's, Bureau of Land Management's (BLM) Public Land Survey System (PLSS).

Each page of this Chicago 80 Acre Map Library website is searchable by either address or PLSS section, township, range and quarter-section designation, and contains detailed survey information such as:  block numbers, subdivision descriptions and designations, lot line numbers and dimensions and address delineations.

Alternatively the full 80 Acre Map Library can be viewed & searched interactively in our online mapping viewer.