But as I keep watching them, I have noticed some... errors. Not deviations from the novels (lots of those), but errors in the movies themselves.
For example, big cities such as Minas Tirith will be full of people (and horses), but there's no farmland around the city to provide food for them. Same with Edoras, the capital of Rohan. I'm not sure if Tolkien talked about farmland around those cities (it's been a while since I've read the books). The Shire seems to be, in the movies, the only place growing food.
There are other errors. For example, in The Two Towers, Frodo, Sam, and Gollum are on a ridge overlooking the Black Gate of Mordor. But in Return of the King, when Aragon leads an army to the gate, the ridge has disappeared. Also, in that battle in front of the Black Gate, Aragon and others ride there on horses. But when the battle starts, the horses disappear.
Speaking of horses. When they reach the Mines of Moria (Khazad-dûm), they let the horse Bill go because he can't go through the mines. But that horse has never been with them before since leaving Rivendell. In the novel, Bill is with them after they leave Bree.
In The Two Towers, a Uruk-hai climbs up on a big boulder to start the battle. But later when Gandalf leads the Rohirrim against the Uruk-hai, the boulder is gone.
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