Recently, the Institute of Tropical Biology under the Vietnam Academy of Science andTechnology and the Spelaeoclub Berlin (Germany) conducted a preliminary survey oflava caves in Tan Phu area, Dong Nai province.

Vietnam is a country rich of natural resources and mineral resources which play an important role in ensuring national energy security and socio-economic development. Among the potential solutions to the sustainable exploitation of natural resources, mineral resources is the harmonisation of exploitation and conservation of the national natural and geological heritage to promote tourism - smokeless industry with high economic efficiency.

Co To island district in Quang Ninh Province has a population of nearly 6,000 people. It is the tourist destination attracting many domestic and foreign tourists. Preserving landscape and environment is one of the key matters in attracting visitors. However, finding out appropriate model of wastewater treatment is not so easy, especially in Co To Island which is far away from the mainland.

Located in Dong Hoi, Quang Binh Province, cave systems of Phong Nha – Ke Bang is about 50 km northwest of Phong Nha - Ke Bang National Park in the districts of ​​Quang Ninh, Bo Trach and Tuyen Hoa and Minh Hoa. The formation of the Phong Nha – Ke Bang karst began over million years ago. In Phong Nha – Ke Bang has about 300 large and small caves with hidden beauties of nature. For scientists, Phong Nha - Ke Bang is known as "a kingdom of cave" with the value of geology, geomorphology and biodiversity.

The aquaculture has been threatened by the uncontrollable industrial production development which has caused serious pollution everywhere.

Ha Giang Province is famous for Dong Van Geopark which is recognized as a Karst Plateau Global Geopark by UNESCO.

In late fall, coming to the Mekong Delta to experience trekking on the mountains is a good choice for visitors.