Visiting the large beaches of Cat Co and Cat Dua, which are separated by a small range of mountain, you can swim in the blue and warm water, so clear that you can see the golden sand bneath.
If you do not want to swim at this crowded place, you can hire a motor boat to sail to the small islets, where there are calm and clean beaches, such as the Cat Trai Gai, Duong Gianh and Hien Hao.
 
The mountain adjacent to Cat Co Beach has a tunnel and fascinating caves and grottoes, such as Hang Luon, Khe Sau, Trung Trang, Gia Luan and Kim Cuong. Visiting these caves and grottoes you will get the feeling of the explorers, discovering the wonders and mysteries endowed by nature. The fauna living on the Cat Ba National Park is diverse: 20 kinds of animals, 69 kinds of birds, 20 kinds of  reptiles, rare wild white - headed langurs.
 
Coming out of the caves and grottoes you should spend a little time to contemplate the sunset over Lan Ha Bay. On the golden background of the horizon and the dark blue of the sea, the heaving islets become multiform, the white sea-gulls hover and sea-eagles make circles in the sky, all beautifying the immense and fascinating space, and enchanting the visitors.

Cat Ba Island is a tourist spot, attractive for its natural beauty and wonders endowed by nature.