Samuel de Champlain's map of Saco Bay, the Saco River, and surrounding area contains numbers in the water for depth soundings in fathoms. The letters describe the topographical features as well as general information about the Native population.

Many of the items described on the map are spelled phonetically, including the name of the Wabanaki river name translated into a French version - "Chouacoit". This is especially important because it is one of the few detailed descriptions of where and how Native people lived and farmed along the Saco River.