Alhambra

A towering fortress of steel, stone, and ancient organic matting built atop a jagged thrust of rock by the same name. Located in the northern Nasheenian city of Rioja.

From GOD'S WAR:

Rhys took what was left of his money and his ravaged body and shared a bakkie with eight other hard-luck passengers to Rioja, a northern city, closer to the sea. Towering above Rioja was the Alhambra, a fortress of steel, stone, and ancient organic matting built at the top of a jagged thrust of rock of the same name. Rhys painted portraits in the cobbled square that lay in the shadow of the Alhambra. He sold them for ten cents apiece. At night, he slept in the steep, narrow streets among creepers, black market grocers, and junk dealers.