U.S. sailors in are making history as they race across the Florida Straits to Cuba.

An amateur race billed as the "Havana Challenge" is taking place for the first time with U.S. government authorization thanks to the historic easing of tensions that began in December.

Five 13-foot catamarans departed early Saturday from Key West. They were expected to reach Marina Hemingway in Havana by sunset — and perhaps sooner if strong winds in the 90-mile-wide Florida Straits helped them gain speed. They planned to race Cuban sailors on Tuesday.

Organizers have staged the race in the past without government permission, making it technically illegal. Organizer Joe Weatherby says they received a Commerce Department license this year and now hope to make it an annual event.