JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&amp;sensor=false&amp;libraries=geometry"></script>
<pre id="output"></pre>

JavaScript

var home = ['London', new google.maps.LatLng(51.5, -0.1167)];

var pts = [
        ['Prague', new google.maps.LatLng(50.08, 14.43)],
        ['Paris', new google.maps.LatLng(48.856614, 2.3522219000000177)],
        ['Berlin', new google.maps.LatLng(52.52000659999999, 13.404953999999975)]
];

var output = '';

var dist = google.maps.geometry.spherical.computeDistanceBetween;

pts.forEach(function(pt){
    output += home[0] + ' to ' + pt[0] + ': ' + 
        (dist(home[1], pt[1])/1000).toFixed(1) + ' km\n';
});

document.getElementById('output').innerText = output;