Demonstrates overlays.

The popups are created using Popovers from Bootstrap.

<!DOCTYPE html>
    <link rel="stylesheet" href="https://openlayers.org/en/v5.3.0/css/ol.css" type="text/css">
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
    <script src="https://code.jquery.com/jquery-2.2.3.min.js"></script>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
      #marker {
        width: 20px;
        height: 20px;
        border: 1px solid #088;
        border-radius: 10px;
        background-color: #0FF;
        opacity: 0.5;
      #vienna {
        text-decoration: none;
        color: white;
        font-size: 11pt;
        font-weight: bold;
        text-shadow: black 0.1em 0.1em 0.2em;
      .popover-content {
        min-width: 180px;
    <div id="map" class="map"></div>
    <div style="display: none;">
      <!-- Clickable label for Vienna -->
      <a class="overlay" id="vienna" target="_blank" href="http://en.wikipedia.org/wiki/Vienna">Vienna</a>
      <div id="marker" title="Marker"></div>
      <!-- Popup -->
      <div id="popup" title="Welcome to OpenLayers"></div>
      import Map from 'ol/Map.js';
      import Overlay from 'ol/Overlay.js';
      import View from 'ol/View.js';
      import {toStringHDMS} from 'ol/coordinate.js';
      import TileLayer from 'ol/layer/Tile.js';
      import {fromLonLat, toLonLat} from 'ol/proj.js';
      import OSM from 'ol/source/OSM.js';

      var layer = new TileLayer({
        source: new OSM()

      var map = new Map({
        layers: [layer],
        target: 'map',
        view: new View({
          center: [0, 0],
          zoom: 2

      var pos = fromLonLat([16.3725, 48.208889]);

      // Vienna marker
      var marker = new Overlay({
        position: pos,
        positioning: 'center-center',
        element: document.getElementById('marker'),
        stopEvent: false

      // Vienna label
      var vienna = new Overlay({
        position: pos,
        element: document.getElementById('vienna')

      // Popup showing the position the user clicked
      var popup = new Overlay({
        element: document.getElementById('popup')

      map.on('click', function(evt) {
        var element = popup.getElement();
        var coordinate = evt.coordinate;
        var hdms = toStringHDMS(toLonLat(coordinate));

          placement: 'top',
          animation: false,
          html: true,
          content: '<p>The location you clicked was:</p><code>' + hdms + '</code>'