Caballo Island Caballo Island Caballo Island (which means "Horse Island" in Spanish) is a bluff, rocky island located at the entrance to Manila Bay in the Philippines. It is about long with the highest elevation at 381 feet high. Caballo, along with the larger Corregidor (2 km to the north), divides the entrance to the bay into two broad and deep channels, known as the North and South Channel. The whole island was formerly occupied by Fort Hughes, a U.S. defense fortification before World War II. It was heavily bombed during the war. Caballo and Corregidor Islands are believed to be the
Caballo Mountains Caballo Mountains have few large intrusives, and as a result, hydrothermal mineralization is not extensive. Nevertheless, prospecting in the range began in about 1883, and several mines opened in the first decade of the 20th century. Production has been concentrated in three areas: It has been estimated that the total value of copper, silver, gold, and lead produced from the Caballos before 1952 did not exceed $200,000. At present, more fluorspar is produced than any other mineral. The largest fluorspar deposits are found in Precambrian granite, and jasperized Fusselman Dolomite. As is the case with many other mountain ranges in