Although this island is owned by two countries, there is no real borderline. There are only monuments and signs that delineate the border. Over 350 years ago the two countries decided that residents of either country could travel across both sides of the border without worrying about any trouble. The two countries live peacefully without difficulties which increases tourism. Any separation is more from separate and dissimilar utilities systems, e.g., power on French side is 250V 50 Hz, while the Netherlands side is 110/120 60 Hz. In addition, one must take special care when dialing from the French to Dutch or Dutch to French side as it is, in effect, an international call and requires special dialing instructions. These instructions are typically posted at hotels and tourist locations. The Dutch side, Sint Maarten, is much more heavily developed than the French. It has become a leading destination in the real estate market with more and more developments being constructed. There are high rise condominiums and waterfront communities, all of which are popular to buyers, especially American. Tourists on the streets are frequently approached by timeshare offers for them. The language on this side of the island is English and the de facto currency is the US dollar. Note that grocery stores and other local businesses may have prices expressed in Netherlands Antilles Florins (NAF). The US dollar will be gladly accepted at these establishments as well. Many large resorts have been built and on many days cruise ships flood Phillipsburg with their passengers. Phillipsburg is one of the Caribbean's best shopping towns. If shopping's not your thing, you can sit out back on Phillipsburg's harbor beach and have a drink. Or play at one of the casinos just down the street. There are nine on this side. When it all gets too mellow, go rip it up with a 4x4 excursion around the island.The French side, Saint Martin, consists of the Northern two-thirds of the island. It is governed by the neighboring island of Guadaloupe, and is more European than the Dutch. The native language is French and has the same guiding laws as France. There are no casinos on the French side. It is less developed than the Dutch side, but contains more of the island's natural wonders. The French side is popularly known for clothing-optional Orient Beach and the adjacent nudist resort, Club Orient.
http://www.cluborient.com/home.html However the towns of Marigot and Grand Case provide some of the best gourmet meals anywhere and plenty of interesting shops. Beauty abounds on the island, with bluffs overlooking pretty harbors, sandy-cliffed beaches or just tranquil rocky coves where fish provide the beauty. Neither country, and side of the island would be able to stand on its own without the other. http://wikitravel.org/en/Saint Martin