In the books
In the A Song of Ice and Fire novels, Bayasabhad (also known as the City of Serpents) is one of the fabled lands of the mysterious east, along with Asshai, Yi Ti, and the plains of the Jogos Nhai. Like its sister cities Kayakayanaya and Shamyriana, Bayasabhad was once part of the Patrimony of Hyrkoon, a civilization that flourished in eastern Essos thousands of years ago, but has since fallen. The warriors of these three cities are all women, since the people believe that only those who bring life into the world have the right to take it away. These female fighters are skilled in a variety of weapons and are taught to ride before they can walk. They are also famous for fighting bare-brested, wearing iron rings in their nipples and ruby studs in their cheeks.
Bayasabhad and its sister cities are ruled by men known as the Great Fathers, and they are the only men in the cities who are allowed to breed. It is said that ninety-nine out of every one hundred boys are gelded when they reach the age of manhood and live out their lives as eunuchs, serving as scribes, priests, scholars, servants, cooks, farmers, and craftsmen. If a male is particularly tall, strong and attractive, he is spared and may become a Great Father in his turn. The origin of this tradition is not fully understood in Westeros, though Maester Naylin speculates on the reasoning behind it in his work Rubies and Iron.
The Lands of Ice and Fire map book- which features a significantly different outline of eastern Essos than the TV series- places Bayasabhad and its sister cities just east of the Bones, an immense mountain range that runs from the northern (Shivering Sea) to southern (Jade Sea) coasts of Essos. Three major thoroughfares- the Steel Road, the Stone Road and the Sand Road- form the main passageways through the range, each commanded by a city. Bayasabhad, the southernmost of the three, sits astride the Sand Road.
The Further East of Essos