Cuba has long been the forbidden island, a tropical bastion of communism whose mystique was amplified by the fact it was largely off limits to Americans. Now, as part of the détente between the United States and Cuba, Americans wishing to go there will face fewer restrictions, provided their visit is "purposeful" (strictly sun-and-sand holidays are still prohibited). The opening comes as life on the island is gradually changing — not fast enough for many Cubans, but slowly enough that those wanting to glimpse a crumbling socialist system, see the miles of undeveloped, glittering coastline and strike up a conversation in the back of a battered Oldsmobile still have time. While the issue of travel there is still politically polarizing in the United States, the travel industry is embracing this potential new Caribbean destination with full force. The good news, for Cubans and their visitors, is that the economic reforms — however limited — have created a constellation of privately-run restaurants and bars in Havana and provincial towns, many of them in beautiful, restored homes. An effort by the government to reinject life into Havana’s cultural scene has spawned vibrant new venues like the Fabrica de Arte Cubano, where the young, hip and better-off line up on weekends. Given the sharp rise expected in the number of Americans visiting, travelers should book early if they want somewhere to sleep during the 12th Havana Biennial, May 22 to June 22, an event that — as if to prove Cuba still operates at its own pace — rarely happens at two year intervals. VICTORIA BURNE