SHENZHEN —?Thirty couples were invited to take free wedding photos Monday in China's largest nuclear power base, according to the parent firm, China General Nuclear Power Corporation (CGN).

The couples were chosen from nearly 3,000 couples nationwide who applied for wedding photography at the Daya Bay plant. Monday also marked the 30th anniversary of start of the plant's construction.

They also visited the reactor's cutting-edge neutrino experimental station.

The two-day visit was part of a CGN three-month promotion to show the base's scenery and introduce people to nuclear power.

CGN said it would receive 100 couples for wedding photography every year in the future.

Data from the Ministry of Environmental Protection showed that the radiation levels and biotic population within 10-km-radius of the plant have not changed in 30 years.

As of Monday, nearly 600,000 people had visited the base since it started public open days in 2013.

CGN is China's largest nuclear power operator and the largest nuclear power builder worldwide. It focuses on the development of clean energy such as nuclear power, nuclear fuel, solar power and wind.

Located in southern China's Guangdong Province, the Daya Bay nuclear power base has six generation units from two nuclear power plants and can generate 45 billion kwh of electricity annually, supplying clean power to Guangdong and Hong Kong.