Many of the biggest movies in Hollywood are based on historical events, meaning factual-based mistakes are often made, especially with costumes.

Braveheart, Gladiator and Pirates of the Caribbean are just a handful of movies that have caused uproar with their inaccuracies.

Here are a collection of shocking mistakes from some of the biggest movies ever:

Back to the Future

During the prom scene in 1955, McFly(Fox) was strumming a Gibson ES-345 guitar even though these were not made until 1958.