Casino operator Harrah's Entertainment Inc. (HET) and Starwood Hotels & Resorts Worldwide Inc. (HOT) said Monday they are joining forces to build the largest resort in the Caribbean at a cost of $1.6 billion.

The Baha Mar (search) "resort metropolis" will be located on Nassau's Cable Beach area of New Providence Island and offer a massive casino and six hotels with a total of 3,550 rooms.

Set to open in 2010, the resort is a direct challenge to Kerzner International Ltd.'s (search) nearby 2,300-room Atlantis on Paradise Island in the Bahamas.

Harrah's, which bought rival Caesars Entertainment (search) this summer, is to build a 95,000-square-feet Caesars casino — the size of two football fields — at the resort. Starwood will build and run hotels under its Sheraton, Westin, W and St. Regis brand names. Privately held Baha Mar Development Co. will run services tying the resort together.

Baha Mar will lead the investment, with 57 percent, followed by Harrah's with 33 percent and Starwood with 10 percent.

The resort — aimed at young adults, families and convention customers — will feature an 18-hole golf course, long beachfront, 55-foot-high waterfall and a network of canals connecting the casino, hotels, shops and open-air restaurants. The resort's design team also worked on the Bellagio and Wynn resorts in Las Vegas.

Harrah's shares rose 65 cents to $63.98 on the New York Stock Exchange, while Starwood rose 1 cent to $58.60.