The photograph is the Knollwood Club, 1890 Knollwood Road, Lake Forest. The photo is of the pool and its surrounding buildings. The pool has a diving board, lawn tables set up around it. Two visible buildings near the pool. On the back, the photo was by Ward McMasters and a stamp on the bottom also says Edward Arpee of 383 Washington Road LF.
from the Knollwood Club's website- The swimming pool was financed by a group of men who rented the cabanas on five year leases and thus provided enough money for construction.
2005.65.5 is the same photo