JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cityathletic.co.uk/dev/wp-content/themes/cityathletic/_assets/javascript/tile.stamen.js?v1.2.0"></script>
<div id="map"></div>
<script src="http://maps.googleapis.com/maps/api/js?key=AIzaSyAFlsKxTq2e05kuip4MCOJrBHAZg4cfHc8&sensor=false"></script>
<script src="http://maps.stamen.com/js/tile.stamen.js?v1.2.1"></script>

CSS

#map{
    width: 500px;
    height: 500px;
}

JavaScript

var layer = 'toner';
		var map = new google.maps.Map(document.getElementById('map'),{
			center: new google.maps.LatLng(51.514635,-0.092992),
			zoom: 15,
            mapTypeId: layer,
			scrollwheel: false,
			disableDefaultUI: true,
			mapTypeControlOptions: {
				mapTypeIds: [layer]
			}
		});
		map.mapTypes.set(layer, new google.maps.StamenMapType(layer));
		var marker = new google.maps.Marker({
			position: new google.maps.LatLng(51.499405,-0.390596),
			map: map
		});