Nothing in this chapter shall be construed to authorize the annexing of territory of one county to a neighboring county, where the territory proposed to be annexed, or any part thereof, is at a greater distance than ten miles from the courthouse in the county seat of the county to which said territory is proposed to be annexed, as said courthouse is now located, nor to authorize the annexation of any territory at a greater distance than three miles from high water mark of tide water, but such annexation shall be strictly confined within said limits.
RCW 36.08.100