The Great Santo Tomás Cavern, the largest cave system in Cuba, is located in the western province of Pinar del Río, in the Mogotes Valley, close to the tourist city of Viñales. It is in the rural Moncada area, a community of unusual brick houses surrounded by fine grass and fruit trees. The cavern has more than 45 km of galleries and was called the "Princess" of Cuban caves by the great Cuban geographer, spelunker, and archaeologist Antonio Núñez Jiménez (1923-1998), who made his first expedition to the cave in 1954.
Núñez Jiménez was the first president of the Cuban Academy of Sciences and founder (on January 15th, 1940) of the Spelunking Society of Cuba, and later of the Spelunking Society of Latin America and the Caribbean. The National Spelunking School is in a singular space between two hills, and from its founding in 1984, the Great Santo Tomás Cavern became a base of study and training for new generations of Cuban spelunkers. Recently, a group of Cuban, Puerto Rican, Brazilian, and Costa Rican specialists decided to stay for a number of days at the National Spelunking School. For those unfamiliar with the Santo Tomás Cavern, it was quite surprising to walk amid its gigantic columns, stalagmites, and stalactites and cross some of the underground canals that in rainy seasons are abundantly full and vigorous.
This Cuban cavern system is greatly admired by spelunkers, not only for its extensiveness, but also for its beautiful and varied formations.
Its name comes from the huge underground galleries formed by the Santo Tomás stream and tributaries of the Caoba River that flow into the Cuyaguateje River. The exploration and study of the Santo Tomás Cavern is an important part of the history of Cuba's Spelunking Society, which began underground research in the Quemado Mountains 14 years after its foundation.
A study of Pleistocene era fossils revealed that it was formed in the periods before the settlements of pre-Columbian native communities.
The location of such caves as the Salón, Dacal, Cristales, La Vela, Represas, and more than 40 others give testimony to the hard work carried out over the years by Cuba's Spelunking Society.
Many others discovered halls and galleries including Chocolate, Salón del Caos, Insistencia, Musical, Arco, Tinieblas, Perlas, Catibo, Conexión, and Flores de Yeso. All of these places together make up the Great Santo Tomás Cavern, whose many cavities are often accessed through holes, of which the most famous for its location and links with several openings is the Hoyo de Fania. According to legend, the Hoyo de Fania is named for a fugitive slave named Fania who, together with other runaway slaves, sought refuge in the Tambor Cave.