The Siege of Gondor is the 4th chapter in Book 1 of The Return of the King. * IV - The Siege of Gondor - the great armies from Mordor arrive at Minas Tirith and besiege it with catapults, siege towers, trenches, and Grond finally which smashes the Gate of Minas Tirith. The siege is lead by the Witch-king, who confronts Gandalf, who is on his horse with Pippin, on the Second Level of the city right before the horns of the Rohirrim are heard from the north. The chapter following takes place several hours before the end of Chapter 8; of Theoden's and his armies' long ride to Minas Tirith.