If it is not Sunday (when most of the French side/except the beaches is closed):
The capital of Marigot, has a nice French Riviera appeal with shops and sidewalk cafes. Overlooking the harbor on a hill is Fort. St. Louis. Grand Case is located on a pretty bay with a secluded beach overlooked by waterfront restaurants. Good swimming, but not snorkeling, except for some large starfish. Orient Beach overlooks a beatiful vista, and has two sides. The clothing optional side on the east is well marked. Lots of chairs for rent and a few places to get a beverage or food. I have found snorkling fair here, with conch shells. Lots of unclothed people walking on the beach.
To the west of the demarkation line, the beach has many beach restaurants, rental chairs and umbrellas, and some watersports. Remember, this is a French beach, so even on this side there may be some topless beachgoers.
There is a beach just east of Orient Beach, just a few blocks further down the road from the butterfly farm that was secluded and not crowded, a restaurant and chair rental. Snorkeling was to the left a good walk around on the rocks. From my review of my visit there 12/02: "Taxi to La Galleon beach on the French side, east of Orient Beach, which we had found on the internet was $18 for up to 3 persons, each way. Arranged for taxi to return to pick us up. This was a nice uncrowded beach. Fair snorkeling, great windsurfing and sail boarding. No hustle by vendors. Seemed like locals using it. Chair rental was $5. There was a restaurant and bar, and restrooms available. Tops optional."