Tres Marías, Las (läs trās märēˈäs) [key], archipelago, in the Pacific Ocean, c.60 mi (100 km) W of Nayarit state, Mexico. Of the four islands, two—María Madre, which is the largest (c.56 sq mi/145 sq km) and is also a federal penal colony, and María Magdalena—produce maguey, salt, and lumber.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.