An old Danish colony!
Back in 1917, Denmark sold the three islands of St. Croix, St. John and St. Thomas to USA for USD 25 million. Today, the islands are massive tourist destinations with cruise ship visits every day.
Back then, slavery was a big thing for Denmark, and today the islands still show a lot of the past history. My favorite islands is St. Croix, where I spent 3 weeks during off season to really get a feel of what it's like living there now.