Delkos (Ancient Greek: Δέλκως), or Delcus, was a town of ancient Thrace.[1] Under the name of Delcus it was a bishopric and later a titular see, now suppressed, of the Roman Catholic Church.[2] It was later called Derkos, under which name it again was a bishopric and later a titular see of the Roman Catholic Church.[3] The Orthodox diocese remains extant (see Metropolis of Derkoi).