St Thomas is called the Rock City because it is one big mountain. Its main town is Charlotte Amalie, the coastline is made up of private beach resorts. St Thomas is the most populated of the three US Virgin islands.

The Dutch West India Company established a post on Saint Thomas in 1657. The Danish conquered the island in 1666, and by 1672 had established control over the entire island through the Danish West India and Guinea Company.

In 1917 St. Thomas was purchased along with Saint John and Saint Croix)by the United States for $25 million, as part of a defensive strategy to maintain control over the Caribbean and the Panama Canal during the First World War.

There are a number of tourist attractions, Coral World an underwater coral observatory and Mountain top the highest point on the island.