ORS § 201.110
The boundary of Gilliam County is as follows: Beginning at a point on the boundary of the state opposite the mouth of the John Day River; thence up the middle of the main channel of John Day River to the intersection of such channel with the south line of section 6, township 6 south, range 19 east; thence easterly along section lines to the east line of township 6 south, range 24 east; thence northerly along the east line of such township to the south line of township 5 south, range 24 east; thence easterly to the southeast corner of such township; thence northerly to the northeast corner of such township; thence westerly to the northwest corner of such township; thence northerly to the northeast corner of township 4 south, range 23 east; thence westerly to the range line between ranges 22 and 23 east; thence northerly along such range line to the boundary of the state; thence westerly along the boundary of the state to the place of beginning.
ORS 201.110