This natural dam is still growing as sulphurous waters seep through the rock. Located near Battleship Rock at the head of Jemez Canyon. The canyon's archaeological high point is Jemez Pueblo which was a religious center for ethnic refugees in the 1630's. The locals do not welcome visitors. Nearby the Jemez State Monument preserves the ruins of the Giusewa Pueblo and the fortified mission church San Jose de los Jemez.
Interpretive exhibits tell the unpleasant history of the area.