The great features of this province are the immense plains on the ridge of the Cordillera, elevated from 6561 to 8857 feet above the level of the sea, and forming bases for still higher mountains, whose hoary heads repose on their bosom. These plains are from fifty leagues in length, to ten in breadth. The mountain of Toluca, the highest summit of the intendancy, is covered with snow, whence it is called Nevado de Toluca; the word _nevado_ signifying a mountain which rises above the lowest term of congelation. The highest peak of this volcano is 15,156 feet in height, the plain on which it rests being itself 8857 feet above the level of the sea. The mountains surrounding the vale in which Mexico is situated, are all very high, but reach the greatest elevation on the south, where the intendancy of Puebla begins, in which are two great volcanoes close to the boundaries of Mexico. The Iztaccihuatl and Popocatepetl roads of communication cross the crest of the Cordillera, enclosing the valley in six directions; one road passes between the last named volcanoes, and consequently, through very sublime scenery, another road, which is not yet finished, leads from Mexico to Vera Cruz, and promises to give great energy to the commerce of the interior countries. Some idea may be formed of the labour and art employed in opening these extraordinary communications, when we find that some of them are carried over summits elevated near 10,000 feet above the sea, at a greater altitude than the lower limit of perpetual snow in central Europe, and at nearly the height of Mont Perdu, the highest peak of the Pyrennean chain. On the plate of comparative heights of the American Cordilleras which accompanies this work, a glance will suffice to point out these stupendous undertakings. The lakes of Mexico are fed by small rivers, which rise in the surrounding mountains.