High level points in the gravity field occur at the head of Yass River just north of the east finger of the ACT of –320 μm·s−2. 1 μm·s−2 is 0.1 milligals, so this level is –32 milligals. Another high of –330 μm·s−2 is just north of the northernmost point of the ACT. The contours in the ACT run NW–SE. At the Canberra GPO is about −440, at Scriviner Dam −510, at Lake Tuggeranong Dam −600, and Banks −590. The western end of Kambah has the lowest level in Canberra at −610. Oaks Estate is −400, the highest levels in the metropolitan area are at Watson and Mitchell at −350, and at Mulligans Flat at −345. This means that a 50 kg person, if measured on a force scale rather than on a balance, would apparently weigh 1.3 grams more in Watson, than they would in western Kambah.