We were in time for the 11:00 tour of the mansion. (No interior photography is allowed.)
The grounds and the gardens are beautiful.
Also at Cantigny: the First Division Museum. It chronicles the history of that unit ("the Big Red 1") from the Revolution to Desert Storm. There are walk-through exhibits replicating a WWI trench, a WWII camp, and a Vietnam War camp. Outside are two dozen tanks.
Cantigny's operation is supported by the McCormick Tribune Foundation. Admission is just $5.50 per car for parking. We enjoyed lunch outdoors at the Cantigny restaurant.
We thoroughly enjoyed the day's outing, and we were home by 3 p.m.!