Four geological sites of exceptional scientific and educational importance, rarity or beauty have been added to the Global Network of National Geoparks, a United Nations-backed list launched to promote greater cooperation in the management of the world’s geological heritage.

The new members – selected by the Bureau of the Global Geopark Network at the three-day 11th European Geoparks Conference in Portugal this week – come from China, Indonesia, Hungary and Spain. The network, launched with the backing of the UN Educational, Scientific and Cultural Organization (UNESCO), now has 91 sites from 27 countries.

To qualify, sites must not only be of scientific importance, but should also possess an effective management structure which allows for sustainable development, with a particular emphasis on sustainable tourism.

The chosen sites this year include the Bakony-Balaton Geopark in Hungary, which is home to old crystalline rocks from several hundreds of millions of years ago, as well as hot springs, volcanoes and sharp cliffs, making it a significant area of geological study.

The Batur Global Geopark, located in northeast Bali, also made the list. The site is centred around the Batur volcano, which is still active and forms part of a long chain of similar volcanoes in Indonesia. The area lies between two large volcanic craters that formed about 22,000 years ago and is rich in elements of macro and micro-volcanic landforms produced by the volcano across several thousands of years. In addition to the scientific value of the site, the park also showcases specific customs related to the Balinese Hindu religion.

The Central Catalonia Global Geopark in Spain, also a new addition to the list, has an extensive geodiversity, including sedimentary rocks showing multiple examples of rich diverse life from past geological eras. It is also known for the abundance of marine fossil which originated from organism living in warm shallow seas which covered the region 55 million years ago.

Another new site is the Sanqingshan Global Geopark in China located in the Jiangxi Province, which possesses a unique blend of granite geology, landscape and wildlife. The Geopark, provides a cultural history spanning 1,600 years, and is considered an outstanding example of harmonious co-existence of nature and people, influenced by the traditional Taoist culture. The park has inspired many painters, photographers and sculptures and is considered to be the cradle of Gan Opera, which encompasses a wide variety of vocal styles.