At the time of the mission to destroy Thread, a ninth Weyr was
proposed to relieve the overcrowding in every one of the older Weyrs. A
favored site was examined at the eastern end of the Western Barrier Range.
On the western shore of the Caspian Lake, at the confluence between
the edge of the wide Rubicon River and the small inner sea, a small body
of water full of granite cliffs that once housed Xanadu stakehold. Wide
stone steps were cut in the granite leading down to the lake shore.
The dwelling itself had been built of the native stone. Its chimney
stack still stood into the Ninth Pass. The imperssive vista in the sheltered
valley and the broad lake with the interesting chimneylike islets would
make a good weyr when Thread no longer fell.
Excerpt from Dragonlover's Guide to Pern
2nd Ed. by Jody Lynn Nye.