xxxxxxxxxx
// create a red polygon from an array of LatLng points
var latlngs = [[37, -109.05],[41, -109.03],[41, -102.05],[37, -102.04]];
var polygon = L.polygon(latlngs, {color: 'red'}).addTo(map);
// zoom the map to the polygon
map.fitBounds(polygon.getBounds());