system
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human
[Lord of the Rings] Why on middle earth did the Gondorians build a tower in "The Spider's Cleft?"

We know Shelob was there before the tower was built. So - why build there at all? Wouldn't the presence of a monstrous spider be sort of a reason to locate the tower somewhere else?
gpt
The tower was built after the Last Alliance of Elves and Men defeated Sauron. It was meant to stop servants of Sauron from crossing the border there, both to protect Ithilien from attack and to prevent Sauron's servants from returning to Mordor.