Gaylord Hotels celebrated in a big way on April 25, the grand opening of its newest property, the $865 million Gaylord National Resort & Convention Center, in National Harbor, Md. The largest combined hotel and convention center on the Eastern Seaboard, it has 2,000 guest rooms and its 470,000 square feet of meeting, convention, and exhibit space includes the 50,000-square-foot Potomac Ballroom and the 180,000-square-foot Prince George's Exhibit Hall) On site are seven restaurants and eateries; the 20,000-square-foot Relâche Spa & Fitness Center, with 12 treatments rooms, massage rooms, and a health club; Pose, a nightclub on the 18th floor with floor-to-ceiling windows with dramatic vistas of the Potomac River and Washington, D.C.; and a private marina on the Potomac (water taxi service runs continuously throughout the day).