Looking For The Name Of A Vampire Movie (1970's - Maybe Made For TV)?

There is an old man and a young girl stranded in a mist covered valley, town is in ruins, he holds vampires at bay with an ornate cross, saves a wandering traveler from vamps. Old guy gets attacked/dies of old age, wanderer takes cross and young girl, make a run for it. In the ensuing chase, wanderer loses girl, loses cross, escapes the misty covered valley. Exhausted and disoriented, he hitches a ride with a mail truck with tinted windows - driver takes him back to the misty town where he reveals himself to be a vampire and they all attack him - the end