The million year-old limestone Borra Caves, is situated in Ananthagiri Mandal, about 90kms north of Vizag on the way to Araku valley. The caves, at a height of 1400 mts above sea level and occupying an area of 2 square kilometers is filled with fascinating stalagmite and stalactite formations of calcium deposits. The Gosthani river flows through the caves between the formations. This natural caves were discovered in1807 by William King George of the Geological Survey of India. Among the formations can be found a 'Shivalingam' and an idol of a cow (Kamadhenu) which has given a religious significance to it. The caves are beautiful and are brightly illuminated. The best time to visit the caves is November- December. The Train journey from Vizag to the caves(5-6 hrs) through the thick vegetation of the Eastern ghats is splendid.