This recently discovered grotto is one of the most beautiful in Halong Bay. Thien Cung is situated on the southwest side of the bay, 4 km from the wharf outside of Halong City. It is located in a small range of islands that resemble a throne embracing two superb grottoes at its core. The way to Thien Cung is perilous, covered on both sides by thick forest. After entering a narrow gate, the magnificent, 130 m long grotto opens up. According to legend, a beautiful young lady named May (cloud) caught the eye of the Dragon Prince and he fell in love with her. They were betrothed and got married in the very center of the grotto. All of the scenes of their wedding, which lasted for seven days and seven nights, have been seemingly fossilized in the grotto. In the center, there are four large pillars supporting the “roof of heaven”. From the base to the top, many strange images seem to exist in the stone, including birds, fish, flowers and even scenes of human life. On the north wall of the grotto, a group of fairies seems to be singing and dancing in honor of the wedding. Under the immeasurably high roof, stalactites form a natural stone curtain. There is also the sound of a beating drum made by the wind blowing through the stone. In the last chamber of the grotto, a natural gushing stream of water babbles throughout the year. Here there are three small ponds of clear water. One path meanders out of the grotto.