- "They say a thousand slaves died building the Great Pyramid of Meereen."
The Great Pyramid is a massive structure in the city of Meereen. It is the largest building in the city and it is said a thousand slaves died during its construction. At its apex there was a huge bronze harpy until it was taken down.
During the Siege of Meereen, as the local slave population rises in arms against the Great Masters, an enormous black banner with the three-headed red dragon of House Targaryen is placed over the harpy atop the pyramid. After the revolt is victorious and the city falls to Daenerys Targaryen, she takes up residence in the Great Pyramid.
Some time later, the great bronze harpy atop the Pyramid is removed by Unsullied soldiers, sliding down a wooden ramp on the side of the building and crashing to the ground, heavily damaged.
After Dany's flight from the city, the Queen's advisor Tyrion Lannister and his spy master Varys take up residence in the Great Pyramid. Missandei and Grey Worm also help them rule while Jorah Mormont and Daario Naharis search for Dany.
At the Great Pyramid, Varys strikes a deal with the prostitute Vala, who is secretly aligned with the Sons of the Harpy, an insurgent group opposed to Dany's abolition of slavery. In return for revealing that Astapor, Yunkai, and Volantis are funding the Harpies, she and her son are allowed to emigrate to Pentos. The Great Pyramid later hosts negotiate between Tyrion, his advisors, and representatives from the slave cities. They agree to a compromise solution of a seven year period to phase out slavery and compensating former slave owners.
Later, the Great Pyramid hosts a meeting between Tyrion, Varys, and Kinvara, the High Priestess of the Red Temple at Volantis. To convince the Meereenese that everything is being done with Dany's approval, the Red Priestesses agree to preach that Dany is The Prince That Was Promised. Tyrion and his advisors Grey Worm and Missandei are exchanging jokes and drinking at the Pyramid when the slave masters break their pact and bombard Meereen. Later that night, Dany returns and lands with her dragon Drogon on top of the pyramid.
After the defeat of the slave masters and the Harpies, the Great Pyramid hosts a high level meeting between Dany, Tyrion, Yara Greyjoy, and Theon Greyjoy. As a result of this meeting, an alliance is forged between Dany and Yara's Ironborn faction. In return for getting access to a hundred ships and getting the Ironborn to end their practice of raiding Westeros, Dany agrees to help them defeat their uncle Euron Greyjoy and to recognize the independence of the Iron Islands.
In the books
In the A Song of Ice and Fire novels, the Great Pyramid had been built as an echo of the Great Pyramid of Ghis, whose colossal ruins had once been visited by noted explorer Lomas Longstrider. Like its ancient predecessor, the Pyramid has thirty three levels, a number chosen intentionally, since it is considered sacred to the gods of the Ghiscari religion.