<!DOCTYPE HTML>
<title>OpenLayers Simplest Example</title>
<div id='demoMap' style='height:250px'></div>
<script src='https://www.openlayers.org/api/OpenLayers.js'></script>
<script>
map = new OpenLayers.Map('demoMap');
map.addLayer(new OpenLayers.Layer.OSM());
map.zoomToMaxExtent();
</script>