After the conference we traveled around southern Turkey. Our first stop was Pamukkale (cotton fortress/castle) which is one of the most amazing natural wonders in the world. The cliffs are totally white as they are covered with the "calcium hydro-carbonate" deposits from the natural hot spring water flowing over them. They have a dried play-do consistency. At the top of the cliffs are the ruins of the ancient city of Hierapolis. We had a great time walking around both the cliffs as well as the ruins.

The picture below is from the bottom of the cliffs.