The ,square-foot, hour Tampa casino is the fourth largest in the U.S. and sixth biggest in the world. Tampa's gaming floor has over. Think of this as a sort of casino bucket list—25 of gaming's greatest resorts that you should see before Our roundup of the best US casinos from coast to coast!. Behind Vegas, Atlantic City, N.J., is the next biggest center of gambling. . The ,square-foot casino is the fourth largest in the U.S.