Mt. Lantoy was declared as a watershedforest reserve by virtue of Presidential Proclamation no. 414 on June 29, 1994. The initial 7265-hectare protected area was reduced in December 2006 via a new Executive Order issued by President Gloria Macapagal Arroyo, reducing the watershed reserve area coverage to 3000 hectares.
In Philippine mythology, Mount Lantoy is said to be the domain of Maria Cacao, a diwata who lives in a cave in the mountain. Outside her cave grow numerous cacao trees, which are said to be her plantation. After harvest time come rains that wash down the mountain, enabling Maria Cacao to float down to the towns below in her golden ship to sell her products.