Nokrek National Park in the Garo Hills is the core of a UNESCO biosphere reserve. Its thick forest is the home of a wild citrus, Citrus indica, thought to be an ancestor of cultivated citrus fruits, and it shelters hoolock gibbons and red pandas. The usual base is Daribokgre village, from where a trail climbs to Nokrek Peak.

Siju Cave lies beside the Simsang River in the South Garo Hills and is one of the longest caves in India. It is also called the bat cave for the huge colonies that live inside. A stream flows through, so visitors wade in water to see the first chambers with a local guide. A bird sanctuary lies across the river.