Alden ( ), elevation 1,004 feet (306 meters), is an unincorporated community and census-designated place in McHenry County, Illinois, United States. It was named a CDP prior to the 2020 census which showed a population of 113. History Alden was laid out in 1844, and named after Alden, New York, the native home of a large share of the first settlers. A post office called Alden has been in operation since 1844. Geography The community is situated in the heart of Alden Township at the junction of Alden Road (County Highway V-12) and Illinois Route 173. The headwaters of Nippersink Creek originate at the High Point Unit of the McHenry County Conservation District, flowing to the southeast and east. In terms of geographic coordinates, the community is located at (42.4589075, -88.5178757) In terms of the Public Land Survey System, Alden is located within the Southeast Quarter of Section 15 and the Northeast Quarter of Section 23, Township 46 North, Range 6 East of the Third Principal Meridian. Alden is served by the Harvard, Illinois 60033 post office. Demographics 2020 census Points of interest A small commercial district is located at the highway junction. The Alden Township facility is just south of the community at 8515 Alden Road. See also Alden Township, McHenry County, Illinois References Unincorporated communities in Illinois Census-designated places in Illinois Census-designated places in McHenry County, Illinois Chicago metropolitan area