 Earlier, when Pedro Fages and Father Crespí left Monterey they crossed the Encarnacion Arroyo on November 24, 1769, their mission being to explore up the east side of San Francisco Bay, come round the top below Point Reyes and reach San Francisco.What is now known as Upper Penitencia Creek was known in the 19th century as Arroyo Aguaje (an "aguaje" is a spring or watering place; locally variably spelled Aguage or Aguague).A form of the name has been retained by Arroyo Aguague, the principal tributary of Upper Penitencia Creek.