It has borders with the departments of:*Hauts-de-Seine and Val-de-Marne to the north,*Seine-et-Marne to the east,*Loiret to the south,*Eure-et-Loir and Yvelines to the west.
Z odlokom sta se 21. novembra 1969 iz departmaja izločili komuni Châteaufort in Toussus-le-Noble ter se pridružili departmaju Yvelines.