The next is a mountainous district including the greater part of eastern Santa Clara. The fourth comprises the western portion of this province together with all of Matanzas and Havana. The surface of this middle section is largely made up of rolling plains, broken here and there by hills that rise a few hundred feet above the sea level.
The fifth includes the province of Pinar del Rio, the northern half of which is traversed from one end to the other by several more or less parallel ranges of sierras, with mean altitudes ranging from 1,000 to 2,000 feet, leaving the southern half of the province a flat plain, into which, along its northern edge, project spurs and foot hills of the main range.
The highest mountains of Cuba are located in the province of Oriente, where their general elevation is somewhat higher than that of the Allegheny or eastern ranges of the United States. The mountainous area of this province is greater than that of the combined mountain areas of all other parts of the island. The mountains occur in groups, composed of different kinds of rock, and have diverse structures, more or less connected with one another.
The principal range is the Sierra Maestra, extending from Cabo Cruz to the Bay of Guantanamo, forty miles east of Santiago. This chain is continuous and of fairly uniform altitude, with the exception of a break in the vicinity of Santiago where the wide basin of Santiago Bay cuts across the main trend of the range. The highest peak of the island is known as Turquino, located near the middle of the Sierra Maestra, and reaching an altitude of 8,642 feet.
The hills back of Santiago Bay, separating it from the Valley of the Cauto, are similar in structure to the northern foothills of the main sierra. In the western part of the range, the mountains rise abruptly from the depths of the Caribbean Sea, but near the City of Santiago, and to the eastward, they are separated from the ocean by a narrow coastal plain, very much dissected. The streams which traverse it occupy valleys several hundred feet in depth, while the remnants of the plateau appear in the tops of the hills.
East of Guantanamo Bay there are mountains which are structurally distinct from the Sierra Maestra, and these continue to Cape Maysi, the eastern terminus of Cuba. To the west they rise abruptly from the ocean bed, but further east they are bordered by terraced foothills. Towards the north they continue straight across the island as features of bold relief, connecting with the rugged Cuchillas of Baracoa, and with "El Yunque" lying to the southwest.