Siju Cave is located in Meghalaya near Naphak Lane and Simsang River game reserve. It is a limestone cave. The Cave is filled with water and is many kilometers long. It is considered as the third longest cave system in India. In 1927 it was found that the caves have a temperature of 21-26.4 °C.
Arachnida- Opilionida, Schizomida
Myriapoda- Diplopoda Julida, Decapoda Natantia
Crustacea- Isopoda Oniscidea
Collembola- Entomobryomorpha
Insecta- Orthoptera
Some rarest bat species live in these caves.