Nguom Ngao, an astonishing cave with numerous formations, is the most famous limestone grotto in the northern mountain province of Cao Bang due to its distinctiveness and scale.

Visiting Nguom Ngao, you are immediately captivated by its wild beauty when you view it cavernous spaces and impressive stalactites and stalagmites. The formidable echo only adds to the experience.

Nguom Ngao literally means “tiger’s cave” in the language of the local Tay ethnic minority. It is said that a long time ago, many fierce tigers sheltered in the cave and would enter the nearby village to hunt for livestock and even villagers.

The main entrance to the cave is 2km from Ban Gioc waterfall, just off the road to Cao Bang. The wonderful beauty of Nguom Ngao spreads throughout the cavern. A British study in 1995 found the grotto to be 2,144m long, reaching heights of up to 60m, with three main entrances known as Nguom Ngao, Nguom Lom and Ban Thuon.

At its main entrance you can feel the fresh, cool air from the natural filtering inside. Nature has endowed the cave with amazing rock formations that resemble humans, trees, plants and mythical animals.

The cave was formed due to the weathering process of limestone mountains by wind and water over many years. As a result, numerous sparkling multi-coloured stalactites hang from the high stone walls throughout the cave system. Along the way are stalactites of various shapes that resemble boats, cacti, forests, and terraced rice fields, reflecting the mountainous regions of Vietnam and the poles and valleys that are said to create a link between the earth and the heavens and the loving bond between men and women.

Nature has been busy with its work over the years to create attractive stone statues, such as those that resemble human forms, forest trees, animals of fairy tales, a huge lotus bulb and even a fairy combing her hair. Stalagmites appear to grow from the ground, but in fact are fed by dripping stalactites that vertical or horizontal. Many locations feature a large cluster of formations to indulge visitors. One of the most impressive stalactite clusters is one that forms an upside-down lotus chandelier, featuring fairies with flowing long hair on the corners. It is nestled a little below the oncoming path for perfect viewing.

Local people discovered Nguom Ngao in 1921, but the cave was not officially opened to tourists until 2006 when paths were built to lead visitors to many corners of the cave. The electricity system is due to be installed, but it's probably sensible to take a torch.

The main cave is enormous, with one branch reaching almost all the way to the waterfalls, where there is a 'secret' entrance. Normally a guided tour will take about an hour and will only go about 400m into the cave; but ask if you would like to see more. A full tour takes about two hours.

Here are some photos of Nguom Nao cave: