var bounds = new google.maps.LatLngBounds();var i;// The Bermuda Trianglevar polygonCoords = [  new google.maps.LatLng(25.774252, -80.190262),  new google.maps.LatLng(18.466465, -66.118292),  new google.maps.LatLng(32.321384, -64.757370),  new google.maps.LatLng(25.774252, -80.190262)];

for (i = 0; i < polygonCoords.length; i++) {  bounds.extend(polygonCoords[i]);} /// alert the center

alert(bounds.getCenter());  //the center is polygon center