Try to tell your average moviegoer what makes this a great film and you might have to describe the art direction and larger than life power of the props, sets and fighting. Tell an "authenticity Nazi" about the liberties that Boorman takes with the historic details, and they will roundly criticize it. Tell a student of Arthurian legends of the differences between "L'Morte D"Artur" and "Excalibur" and they might suspect the story is a dumbing-down of the Arthurian legend for the masses.
And that's simply not the point of "Excalibur".
"Excalibur" is filmed with great care and attention to detail in showing the transition that is symbolic of the Dark Ages making way for the new ideas and Christianity taking root. It's about what the king is all about, and why a king has power in our imaginations. It's about vicious wars giving way to hope, and the danger of complacency and comfort. It's about more than it seems.
John Boorman went through incredible pains to make this movie as exacting as he did, and you can see it. He didn't want to merely retell the well known legend of Arthur and his world. He wanted to illustrate the meaning behind Arthur himself. The sword was merely a connection and metaphor for that power and purpose. In the end, the story was about the myth of the king and how his condition was once believed to be the extension and direct representation of the state of the kingdom he actually ruled.
But forgetting all of that, the movie is cool. It's look and feel is something you never forget. The film has the distinction of showing Liam Neeson and Gabriel Byrne in their first movie roles. Nicol Williamson's Merlin is perfect and left me wanting more of him. And for a high school student just researching the realm of mythical and fantastic literature, this movie was addictive when it first came out. I loved it so much.