Those newly-discovered caves are relatively large in length, with Nuoc Ngam (2,4 miles), Phu Nhieu (1,25 miles), Nuoc Lan (0,7 miles). However, there are some that are shorter, which measure around 0,03 miles to 0,08 miles.

Besides, due to strict military requirements, the crew couldn't discover several new caves in Le Thuy district, which they believe have potential tourism development. (Photo courtesy of Howard Limbert)

One member of BCRA (pictured)

Expedition in Quang Binh is an annual program of the BCRA. This time, the team discovered the largest number of new caves within 20 days. In 2016, the expedition team found a total of 57 new caves in the area.

Cave system in Quang Binh has always been a surprise to the explorer experts. Last year, an underground cave system was discovered at a depth of 0.03 miles, the deeper the cave is, the wider it expands. The discovery made Son Dong a much more mysterious cave to experts and scientists. (Photo courtesy of Howard Limbert)

In the picture is Loong Coong cave, located on top of Son Doong Cave. The only way to reach the cave is to hang down with a rope for around 0.05 miles. (Photo courtesy of Howard Limbert)

"After 5 days exploring in the forest, we were all put under quarantine for two weeks, as on the way from the UK to Vietnam, one of our team members had onboarded the same flight with one COVID-19 patient", Howard recalled.

Fortunately, all 17 of us were tested negative for the virus. However, the pandemic has spoiled BCRA's exploring plan this year. The expert crew flew back to the UK on March 21. The British experts were pictured during their time in Quang Binh centralized quarantine zone.

"We could not dive inside Hang Thung Cave as planned due to COVID-19. We're gonna come back next year to resume our exploration", one expert said. (Photo courtesy of Howard Limbert)