Odessa-Tumbali Cave System
The Odessa-Tumbali Cave System is one of over 300 caves found in Cagayan province, Philippines. It is recorded as the third longest cave in the Philippines with a length of at least 12.60 kilometers, of which only about 7.65 kilometers have been explored and mapped. Its actual length may reach up to 15 kilometers. An active cave with various formations, passageways, lakes, and canals, it provides excellent opportunities for cave photography as well as wet sport spelunking. It is also home to a variety of wildlife.
The cave has 5 different entrances and is considered a difficult cave to explore with its narrow, flood-prone passages. It may be explored with guides from the Sierra Madre Outdoor Club (SMOC). The cave system is called the Abbenditan Cave by local residents.
The Odessa-Tumbali Cave System is found in Sitio Abbenditan in Peñablanca, Cagayan Valley, approximately 8.5 kilometers away from Quibal Village. Its main entrance is about a kilometer east of the road passing through Barangay Abbenditan.
The cave features a variety of geological formations, making it a good subject for photography. It also has different types of passages. An active, flood prone cave, it has many canals and lakes within, which allow for swimming and diving.
From the main cave opening at the base of a cliff, a 6 meter wide passage slopes down, leading to a 15 meter wide swirl chamber approximately 20 meters high. Below the entrance pit is a wide river passage. After 10 meters, the river disappears through a slot and emerges 260 meters away. Some of the interesting calcite formations in the downstream area include the Banawe Gours, a formation that resembles the Banawe Rice Terraces, and the enormous stalactites hanging down in a chamber called the Chandelier Mudroom. There is also a lake in this part of the cave. There are two passages downstream where many bats, swifts, and snakes can be seen: Dia’s Light and the narrower Python’s Retreat. Higher up, there is a 730 meter dry fossil passage which leads to the small but exquisite crystal grotto known as Heaven. There are also some other small grottos in the upstream area.
Cave exploration expeditions
Local inhabitants and treasure hunters for many years only penetrated the cave through its Abbenditan entrance for a short distance. In November 1990, the cave was explored by Loreto Ocampo, Richard Guzman, Bimbo Mabazza, Ralph Bubut Quinan, and Manoling Cepada of the Sierra Madre Outdoors Club (SMOC), who explored about 500 meters of the downstream area of the cave and a portion of a higher dry passage.
Another speleological expedition was undertaken in February 1992 by the cave explorers’ group Speleo Philippines. The seven spelunkers divided into 2 groups, with 1 team exploring the upstream area and the other the downstream. During the 3-day expedition, about 7.65 kilometers of the cave system was mapped. It was also discovered during this expedition that what was then known only as Odessa Cave connected with a cave in Barangay Tumbali. Subsequent to this, the caves were eventually renamed the Odessa-Tumbali Cave System.
- Cagayan Province Profile. 
- Capistrano Francis Y. “Spelunking in Cagayan.” In BusinessWorld, September 17, 2004. 
- Philippine Information Agency. “Cagayan Valley as caving capital of the Philippines.” 
- Speleo Philippines. “Caving in the Philippines.”