Named for local cattle rancher David M. Deter, this post office was a flag station two miles south of the summit tunnel in the Siskiyous on the SP rail line at "old Gravel Pit Spur" one mile NE of Colestin. Grace Deter was the only postmaster. Deter post office's closing, like Siskiyou's, came with the decline of railroad stops and better rural mail service.
Where did they go? Following the mail trail of the DPOs of Jackson County, Oregon (SHS 979.5281 S93 2013)