• Andhra Pradesh’s Erra Matti Dibbalu and the Natural Heritage of Tirumala Hills, including the Eparchaean Unconformity, have been added to the UNESCO Tentative List of World Heritage Sites.
• Erra Matti Dibbalu is a notified National Geo-heritage Monument located near Visakhapatnam, spread over 1,500 acres.
• First documented in 1886 by British geologist William King.
• Globally, only two other similar sites exist — one in Sri Lanka and another in Tamil Nadu.
• The Geological Survey of India (GSI) declared it a National Geo-heritage Monument in 2016.