To register your vehicles and obtain license plates, you must go the Doniphan County Treasurer’s office at the Courthouse in Troy. If you have moved here from another state, you have 90 days to register your automobile. Be sure to take your title, proof of insurance and a verification of the vehicle ID number, which you can obtain at the Wathena Police Department or at the Sheriff’s office next to the Courthouse in Troy. The County Treasurer’s office is open from 8:30 a.m. – 5:00 p.m. Monday – Friday. Phone number 785-985-3831.