Iljar is a settlement on the Cardassian planet Harkoum. Most of its residents who live there do so only temporarily and stay indoors during Harkoum's daylight hours due to the extreme heat. It was the location of a starport that many ships arrived on and left Harkoum from.
In 2377, Grauq arrived in Iljar and waited there for the "Cardassian Woman" (the Iliana Ghemor of the alternate universe) to arrive and steal a ship to leave the planet in. Grauq believed she would steal the Otamawan from the Iljar spaceport in the town and kept a close watch on it. Ghemor later did arrive in Iljar, but commandeered Grauq's own ship, the Githzarai, and used it to leave the settlement. (DS9 novel: Warpath)