At the beginning of the film Maciste jumps into the sea holding an ax. When he is in mid-air he lets go of the ax which can clearly be seen dropping the water some meters away from him. In the next scene, underwater, the ax is back in his hand.
Julia is wearing a bikini type outfit when she escapes from the city but later has a shinny dress on during the horseback ride and for the rest of the movie.
Characters appear in different parts of the set without any explanation as to how they got there.
In the end, when the statue of Maciste (Goliath) is being lowered into place, the two men turning the winch are turning in a direction that would raise the statue instead of lowering it.