A Ramsar Site is a wetland site designated to be of international importance. These wetlands are protected under strict guidelines of the Ramsar Convention on Wetlands. 

• The Ramsar Convention on Wetlands, also known as the Convention on Wetlands, is an intergovernmental treaty for the conservation and wise use of wetlands. 

• The convention, signed in 1971 by UNESCO in the Iranian city of Ramsar, is one of the oldest inter-governmental accords for preserving the ecological character of wetlands. 
• Over 170 countries are now party to the Ramsar Convention. There are over 2,400 Ramsar Sites around the world covering over 2.5 million square kilometres. 

Source: https://www.thehindu.com/sci-tech/energy-and-environment/watch-all-about-ramsar-sites/article33131182.ece