10 Min by car from the Cruise Port. The governor Jørgen Iversen Dyppel led the second expeditionary force from Denmark to St. Thomas, where he arrived on 25 May 1672. There, he began the construction of Fort Christian in 1680, named after King Christian V Fort Christian is at sea level, which it was ideal to ward off attackers with canon fire. In the 18th century, the fort was enlarged and in 1874 added a new entrance with a Victorian clock tower. Being the oldest permanent structure of the US Virgin Islands, the fortress was used as the town center, government and prison building. It now houses the Museum of St. Thomas. The fort is one of seven national monuments in the US Virgin Islands.