Stamen Tiles

Example of a Stamen tile source.

Two layers are composed: the watercolor base layer with the terrain labels.

<!DOCTYPE html>
<html>
  <head>
    <title>Stamen Tiles</title>
    <link rel="stylesheet" href="https://openlayers.org/en/v4.6.4/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://openlayers.org/en/v4.6.4/build/ol.js"></script>
  </head>
  <body>
    <div id="map" class="map"></div>
    <script>
      var map = new ol.Map({
        layers: [
          new ol.layer.Tile({
            source: new ol.source.Stamen({
              layer: 'watercolor'
            })
          }),
          new ol.layer.Tile({
            source: new ol.source.Stamen({
              layer: 'terrain-labels'
            })
          })
        ],
        target: 'map',
        view: new ol.View({
          center: ol.proj.transform(
              [-122.416667, 37.783333], 'EPSG:4326', 'EPSG:3857'),
          zoom: 12
        })
      });
    </script>
  </body>
</html>