The 11 or so kilometers of soft white sand that make up Grace Bay's beach are reported to be one of the best beaches in the Caribbean - in fact in 2011 and 2012, TripAdvisor users voted it the best beach destination in the world. If one was counting large resorts (30+), the presence of such a variety of places to stay would certainly convince you: from the Seven Stars, to Grace Bay Club, Club Med, the Somerset, the Venetian, Windsong, the Alexandria, the Sands or the all-inclusive Beaches, this is the destination for the island of Providenciales, plus there are also many smaller resorts and private residences.
Trying to capture its loveliness is difficult as every image seems similar - it's just so perfect. What is it that makes it great? The reef prevents any large waves so it is calm and safe -- surf lovers can look elsewhere on the island. The waters are a perfect, beautiful turquoise and blue, apparently from the purity of the white sand (which is so fine it acts like a glue on your feet!). There is world-class diving on the wall of the surrounding reef -- it is part of the third-largest barrier reef system in the world. Perhaps its so great because it seems no one has heard of it?
It got its start when Club Med built an exclusive hotel in 1984, and as it was a deserted beach until then, it was idyllic (only nearby Turtle Cove had begun to be developed). 
Note: The Turks and Caicos Islands are part of the British West Indies, a territory of Britain.
Source: TripAdvisor's #1 Turks and Caicos attraction: http://www.tripadvisor.com/Attraction_Review-g147399-d148331-Reviews-Grace_Bay-Providenciales_Turks_and_Caicos.html
http://news.travel.aol.com/2011/04/05/tripadvisor-names-top-beach-destinations/http://www.gracebay.com/
http://www.traveller.com.au/secrets-out-where-to-find-the-worlds-best-beach-1z9f4
http://www.visittci.com/providenciales/about
