Soi Sim Island is located in the south-west of Halong Bay, less than 10 km from Bai Chay Tourist Port and only 700m away from the famous Ti Top Island. This island has an area of only 8.7 hectares.
The rich flora and fauna are nourished by fertile soil and favorable natural conditions. There are abundant of evergreen trees growing and covering the whole island. Soi Sim is surrounded by the ocean, due to this geographical location, the island becomes home to some endemic plant species which hold great value to the ecological system of Halong Bay.