Qarth is a great trading and port city, one of the largest and richest cities in the known world. It is located on the south coast of Essos, on the Straits of Qarth which link the Summer Sea to the Jade Sea. It lies to the south of the forbidding desert known as the Red Waste, which divides the city from the Dothraki Sea to the north and acts as an effective deterrant against Dothraki raids on the city.
Qarth is inhabited by a people known as the Qartheen. Trade is the lifeblood of the city, as almost all trade between the cities and nations of the Jade Sea and the lands to the west (the Free Cities, Slaver's Bay and Westeros) passes through its port. The city's merchants command immense wealth and a power. The city is also famed as being the home of the Warlocks of Qarth, who are feared and respected across much of Essos.
Qarth is located to the north of the island of Great Moraq, with the Straits of Qarth (also called the Jade Gates) dividing the island from the mainland. Although most travel to and from Qarth is accomplished by ship, the city is also linked to other lands by roads. To the west and north-west lie the smaller ports of Qarkash and Port Yhos, and beyond them the farming nation of Lhazar. To the east roads skirt the southern foothills of the Bone Mountains before passing into the nation of Yi Ti, the greatest kingdom on the Jade Sea.
The ancient history of Qarth - such as its status during the days of the Valyrian Freehold - is not known. What is known is that Qarth has become immensely rich and powerful through its dominance of trade along the south coast of Essos.