Tosya District

thumb|Cukurhan.jpg Tosya (), previously called Theodosia (Greek: Θεοδοσία) or Doceia (Greek: Δοκεία) under the Byzantine Empire, is a town in Kastamonu Province in the Black Sea region of Turkey. It is the seat of Tosya District. Its population is 28,963 (2021). It is the home town of the famous Boyner family and the birthplace of Markos Vafeiadis (1906–1992), a famous Greek politician.