Factual errors: The "golden" bell floats far too high in the water after it falls down the cliff and several of the "bodies" it pulls off the cliff are ahead of it in at least one shot.
Factual errors: The Crusades took place after the era of the Vikings.
Factual errors: The devil was not part of the Vikings' religion.
Factual errors: Ten times the number of men shown could not lift the bell of gold; nor could the small raft shown float it.
Revealing mistakes: When the bell falls from its supports the small chains holding it snap. It is no longer attached to the men who are, regardless, pulled down after it.
Factual errors: Gold, like lead, is a soft and non-resonating material. A bell made of solid gold would "clunk" rather than ring.
Continuity: When the Vikings fight the Moors on the beach, they throw spears and shoot arrows killing many Moors. However, none of the arrows or spears can be seen in flight nor can any be seen hitting the Moorish cavalry (who fall and die).
Continuity: When Aly Mansuh is crushed by the golden bell, it rolls onto his body at waist level. In succeeding shots, it is shown laying across his chest.
Continuity: When the crew is climbing up to the bell, the ship is shown anchored in a different place to their landing site, i.e. they landed on a beach yet there is no beach visible below them, just a rocky shore.
Anachronisms: One of the Vikings fighting the Moors on the beach is wearing bright white underpants.
Factual errors: Leaving aside the issue of the sound of a bell made of gold, the bell could not the sound it does. It forms the dome of the building and is covered with concrete and stone which would stop the metal vibrating, absorbing the energy of the sound.