The dog on the show was simply named Dog. While the dog's name was Higgins (one episode was called "Higgins Come Home"), the name was never mentioned by any characters. He appeared in 152 episodes. His last acting role was as the title character in the movie Benji (1974), which was also Edgar Buchanan's last movie.
Based on the stories told to Paul Henning by his wife, who had spent summers in Eldon, Missouri, at a small hotel located near the train station.
During the run of this show, Charley Pratt (Smiley Burnette) was the engineer of the Cannonball, and Floyd Smoot (Rufe Davis) was the conductor. Burnette died during the fourth season, and Floyd took over Charley's duties as engineer, as well as continuing his own duties as conductor.
During the first two years Pat Woodell played Bobbie Jo as a singing bookworm while Billie Jo (Jeannine Riley) was a flirty playgirl. By the end of the run with different actresses, the characters were almost reversed, with Lori Saunders Bobbie Jo as a fun-loving, somewhat man-crazy ditz and Meredith MacRae playing Billie Jo as a quiet girl in search of a singing career.
Christmas episode from season 1 and season 4 are the same scripts with the exception that it has been colorized, and the characters of Billie Jo and Bobbie Jo are played by different actresses. They also added the character of Steve Elliott in season 4.