Kawtchhuah Ropui (literally meaning the great entranceway) is Mizoram’s first site under the protected monuments of Archaeological Survey of India (ASI). It measures about 45 sq. km and has yielded pictographs on over 100 large stone slabs (menhirs), depicting human, animal and floral etchings. Remains of a necropolis and an ancient water pavilion exist, among other artefacts. The ancient dwellers also carved terraces on rocks for settlement: the main excavated site consisting of 15 such terraces. Recently, ASI has discovered neolithic caves near Vangchhia, indicating that the lost civilization could be much older than its initial estimations.