JavaScript
var map = L.map('map').setView([51.492222, 7.414229], 16);
L.tileLayer('http://{s}.tile.openstreetmap.se/hydda/full/{z}/{x}/{y}.png', {
attribution: 'Tiles courtesy of <a href="http://openstreetmap.se/" target="_blank">OpenStreetMap Sweden</a> — Map data © <a href="http://www.openstreetmap.org/copyright">OpenStreetMap</a> — Icons from <a href="https://mapicons.mapsmarker.com" target="_blank">Maps Icons Collection</a> — Marie-Louise Timcke'
}).addTo(map);
map._layersMinZoom=15;
var l1 = L.polyline([
[51.492048, 7.414358],
[51.491026, 7.414712],
[51.490658, 7.415701],
[51.490023, 7.410379],
[51.490878, 7.410068],
[51.490878, 7.410068],
[51.490958, 7.409832],
[51.491466, 7.409671],
[51.491893, 7.410217],
[51.492259, 7.413123],
[51.492682, 7.415465],
[51.492864, 7.415472],
[51.492985, 7.416414],
[51.493306, 7.416400],
[51.493742, 7.416873],
[51.493982, 7.417020],
[51.494098, 7.417152],
[51.494011, 7.417444],
[51.493900, 7.417522],
[51.494211, 7.419097],
[51.494687, 7.419673],
[51.494577, 7.420137],
[51.494804, 7.421618],
[51.494771, 7.421634],
[51.494544, 7.420177],
[51.494447, 7.420193],
[51.493767, 7.420450],
[51.493786, 7.420853],
[51.493619, 7.421087],
[51.493449, 7.420988],
[51.493336, 7.419586],
[51.493633, 7.419557],
[51.493608, 7.419324],
[51.494139, 7.419098],
[51.494099, 7.418631],
[51.493493, 7.418666],
[51.493214, 7.417515],
[51.493149, 7.417461],
[51.492924, 7.416160],
[51.492757, 7.416211],
[51.492540, 7.415138],
[51.492198, 7.414663]
],{ weight: 12, color: '#8bc2a5', opacity: 0.9 }).addTo(map);
var l2 = L.polyline([
[51.492198, 7.414663],
[51.492095, 7.414530],
[51.492048, 7.414358]
],{ weight: 12, color: '#f28d83', opacity: 0.9 }).bindPopup("Start/Ziel").addTo(map);
// create custom marker
var stairs = L.icon({
iconUrl: 'http://datentaeter.de/wp-content/uploads/2016/04/stairs.png',
iconSize: [38, 35], // size of...