The are numerous caves throughout the entire Province but extensive karst phenomena in Mabinay ensured its claim to being the Cave Town of Negros Oriental. Over 400 caves are said to exist in Mabinay. A Dutch-Belgian expedition identified 45 of these, including Odloman (8,870 meters long), Panligawan (143 meters), Pandalihan (282 meters), Baliw (769 meters) Mambajo (326 meters) and Bulwang (155 meters). Spelunkers will also want to explore those found in Bayawan City and La Libertad.
Balanan Lake in Siaton and Sibulan’s Twin Lakes Balinsasayao and Danao are the centerpieces of Negros Oriental’s biggest and most important ecotourism sites. Other widely-known lakes are Nailig, Halawig and Yagumyum on Mt. Talinis, Valencia; and Kinayan in Guihulngan. The Tirambulo Highland Resort was developed around seven man-made lakes in Paniabonan, Mabinay.