Forget the beach because there isn't one. Abundant reefs, however, are a different story altogether. The island is surrounded by—and zealously preserves—myriad extraordinary dive sites. If you don't dive, there are plenty of shallow reefs you can explore by snorkel.
If you're not into the briny deep, there's always the hike to the top of Mt. Scenery, a breathtaking trip to an even better view, assuming the top isn't shrouded in cloud cover.
Otherwise, it's a quiet and peaceful place and not a half-bad destination if all you want to do is relax and chat with the ever-friendly locals.