From publisher blurb:
The glorious capital city of legendary Hyperborea fell to ruin two thousand years ago in a fiery night of destruction that burned half a continent and heralded the end of an ageless empire. New auguries brought a fellowship of valiant knights to the scorched ruins seeking an ancient danger that threatened the world anew, but those champions themselves disappeared among the broken stones of the shattered city. Now new heroes must take up their mantle, whether to rescue or avenge them, and by all means to complete the their desperate mission to forestall a new cataclysm. However, those daring to tread the ancient streets quickly discover that the ruins do not rest easy, and ancient memories can be as deadly as new perils in Old Curgantium.
Knight Fall in Old Curgantium is a Pathfinder Second Edition adventure for 15th-level characters set in the fabled ruins of the ancient Hyperborean capital of Curgantium in the Lost Lands Campaign Setting. This rich and exciting world 20 years in the making has been home to dozens of adventures from Necromancer Games and Frog God Games and produced with their cooperation to be compatible with The World of the Lost Lands campaign guide! It is the fifth of six adventures in the Aegis of Empires Adventure Path, with each adventure exploring hitherto unexplored areas of the Lost Lands with a combination of horror, intrigue, deadly danger, and the lure of ancient mysteries.