Gulf of Mexico numerous bays and smaller inlets. A number of rivers empty into the gulf, most notably the Mississippi River and Rio Grande in the northern gulf, and the Grijalva and Usumacinta rivers in the southern gulf. The land that forms the gulf's coast, including many long, narrow barrier islands, is almost uniformly low-lying and is characterized by marshes and swamps as well as stretches of sandy beach. The Gulf of Mexico is an excellent example of a passive margin. The continental shelf is quite wide at most points along the coast, most notably at the Florida and Yucatán Peninsulas. The shelf
Xico, State of Mexico Xico, State of Mexico Xico is a city in the State of Mexico, Mexico. It serves as the municipal seat of Valle de Chalco municipality, with which it is, for all practical purposes, coterminous. The municipality lies adjacent to the east side of the Federal District (Distrito Federal) and is part of the Mexico City metropolitan area. The city and municipality lie on the old lakebed of Lake Chalco, which was drained like much of the Basin of Mexico. The city name comes from the nearby Xico hill (Cerro de Xico) and the name of the municipality comes from the