[3] Throughout its length, it shifts between two and four lanes as it passes through a frequently changing setting of scenic forestry and smaller populations, as well as busy intersections and larger developments.

Beginning at its western terminus at a commercially developed intersection with U.S. Route 14 (Northwest Highway),[4] Illinois 22 starts out as a two lane road in Fox River Grove, just inside the McHenry County line.

[5][6] The Advocate Good Shepherd Hospital and Stonehenge Golf Club on the north side are all that lie in this wooded area of sporadic residential development.

[7] Heading into North Barrington, the road continues its journey as it crosses paths with Illinois Route 59 (Hough Street) until soon after, when it nears the more densely populated area of Lake Zurich.

[3] Shortly after, it proceeds to briefly take a northeast direction while it bypasses the narrow, downtown area of Lake Zurich, including a grade separation at the Elgin, Joliet and Eastern Railway (EJ&E).

This all takes place while it narrows back down to two lanes near two housing developments and returns to a rural setting with light forestry.

It passes by more neighborhoods, a shopping plaza on the northeast corner of Buffalo Grove Road, the Arboretum Club, and the Prairie View Metra Station next to the at-grade North Central Service tracks.

[11] The road then enters Lincolnshire and heads nearby the Stevenson High School and an office complex before intersecting with Illinois Route 21/U.S.

[12] Soon the road intersects and forms a diamond interchange with Interstate 94 (Tri-State Tollway); many office complexes and corporate buildings, such as Hewitt Associates, are located nearby.

[13] On the east side of the interchange, Illinois 22 enters Bannockburn as it passes near Trinity International University[14] as well as some upper class real estate areas.

A widespread local legend states that prior to the 1900s, it supposedly took a half day to travel from the area to Chicago, and that this is the source of the name; however, this story has no support in the historical record.

[16][17] In 1918,[2] State Bond Issue (SBI) Route 22 started off as an outer beltway around the Chicago area, similar to the shape of Interstate 294.

[36] Roadwork began in the fall on the two-year project, and in September 2007 it was finished;[37] complete with four concrete lanes and a center grassy median.

Again, intersection expansions were also made, this time adding dual left turn lanes to both east–west approaches at Illinois 83 and Buffalo Grove Road.

[27] Finally, the remaining section located primarily in Long Grove from east of Quentin Road to west of Illinois 83 is also in the works for the near future at an estimated cost of $38.5 million.

If the extension, which is a limited-access expressway and currently terminates three miles south at Lake-Cook Road,[3] were ever built, it would pass through this area, where there would likely be an interchange.