Just 29 kilometres from the bustling city of Da Nang are the majestic Marble Mountains, known as 'Ngu Hanh Son' in Vietnamese, a picturesque cluster of five hills made of limestone and marble, hence the name. These five hills are named after the five elements of nature: Metal, Wood, Water, Fire, and Earth, and a visit to these hills will transport you into a mysterious world of caves and pagodas, both Buddhist and Hindu grottoes, built deep into the mountainside.