Kurald Thyrllan, or Kurald Liosan, was the elder Warren, or Hold, of Light. It was inhabited by the Tiste Liosan, with the city of Saranas as its capital. Kurald Thyrllan gifted the world with Light and Day.
According to L'oric, the Elder Warren had been born of violence, the shattering of Darkness. The shattering of its sister warren had left it twisted and fraught, and difficult to enter. The warren had ultimately branched off in many directions, first creating Tellann, the T'lan Imass warren, and later Thyr, the human warren. Telas, the human warren of fire, was said to be a child of Tellann and thus had its roots in Kurald Thyrllan as well.
Beak observed that Stormy and Gesler were "reforged in the fires of Tellann". He then went on to say:" Telas, Kurald Liosan, the fires, the ones dragons fly through to gain immunities and other proofs against magic and worse".