A visit to the north is not complete without experiencing the spectacular views of more than 3,000 limestone karsts in Ha Long Bay. Declared a World Heritage Site by UNESCO in 1994, Ha Long Bay is a naturalist’s dream. Sculpted into strange shapes by the wind and weather, the karsts hide deserted beaches, many magnificent caves, and hidden lagoons that may only be reached by chinks in the cliffs that are revealed at low tide. The islands in Ha Long Bay are mainly limestone and schist islands most lying in the two main areas: the southeastern part of Bái Tử Long Bay and southwestern part of Hạ Long Bay. These islands represent the most ancient images of a geographical site having a tectonic age of from 250 million to 280 million years. The area is recognized as the World Natural Heritage that is the area of 434 sq. km with 775 islands. It looks like a giant triangle with Ðầu Gỗ Island (in the west), Ba Hầm Lake (in the south) and Cống Tây Island (in the east) as its three angle points. Viewed from above, Hạ Long Bay looks like an extremely vivid huge drawing. This is a wonderful and skilful masterpiece of the Creation and of nature that turns thousands of dumb soulless stone islands into fantastic sculptural and artistic works of various graceful shapes, both familiar and strange to human beings.