The MSC Opera blasted its horn while it ploughed into the dock, but four people have been injured when it crashed into a smaller tourist ship - the "Michelangelo".
Italian media reported that the terrifying incident happened in the Giudecca canal this morning at 8.30am.
At first, tourists on the dock merely jog away from the colossal ship, but as it becomes apparent it is not going to stop they speed up. The deafening noise of the crash lasts for 30 seconds as the hull of the ship meets concrete.
Check it out below.