Meduseld is the name of Théoden’s golden hall in Edoras in J.R.R. Tolkien’s The Lord of the Rings.
The hall is the seat of the king of Rohan and the central landmark of Edoras, the capital of the Rohirrim. Its name comes from Old English and means “mead hall,” fitting Tolkien’s use of Anglo-Saxon language and culture as a major influence on Rohan.
Meduseld is where Gandalf confronts the influence of Gríma Wormtongue over Théoden. After Théoden is restored, the hall becomes a setting for decisions about Rohan’s defense against Saruman and Sauron. Isengard is Saruman’s fortress, while Minas Tirith is the capital of Gondor, so those locations belong to different kingdoms and roles.