Saint Barths
Saint Barths is about a 45 minute ferry ride from Saint Martin. The water can be choppy, but well worth it once you get there. There is an option to fly if you want to arrive faster, although it is on a very small plane. There are some nice beaches here and driving the streets of the island is an adventure to say the least. The shopping is much like that of Beverly Hills full of high-end retailers, and the restaurant selection is of equal stature. If you rent a convertible to explore, make sure you stop near the Gustaf III airport to watch planes land at on one of the most dangerous runways in the world. If you are staying in Saint Martin, this is a great 1-2 day trip full of luxury and adventure.
The Tips
Be prepared for the ferry ride if you get sea sick.
Know the Ferry times, they are on time and will not wait.
Rent a convertible to explore the island.
Bring a lot of money, this is one expensive island.