DuPage County GIS Maps & App Portal

This is the main DuPage County site for directly viewable maps. Some pages of particular interest are:

DuPage County Digital Map Book
This contains most political maps of interest, but the top menu is too wide, so here are all the choices (sorted by relevance to elections):

DuPage County GIS Open Data

Offers downloadable data for digital mapmaking, plus a few interactive applications. Note that some of the selections are packaged searches; to see all datafiles, turn off all search filters at the top of the column on the left or click here.

ArcGIS REST Services Directory

A wealth of datasets, but some skill is required to use them.