 The Hobart Post Office was first opened May 9, 1903 with William Sidebotham as first postmaster  A coal mine also operated in the area as late as 1947.Hobart is located in central King County at (47.415568, -122.005950).It is bordered to the north by Mirrormont, to the northwest by East Renton Highlands, to the southwest by Maple Valley, and to the south by Ravensdale.