> For the complete documentation index, see [llms.txt](https://docs.mapbox.com/mapbox-gl-js/llms.txt)
# Add a vector tile source
Add a [vector source](https://docs.mapbox.com/style-spec/reference/sources/#vector) to a map.
Add any Mapbox-hosted tileset using its tileset URL (`mapbox://` + [tileset ID](https://docs.mapbox.com/help/glossary/tileset-id/)). To find a list of *Default tilesets* provided by Mapbox and *Custom tilesets* you have uploaded to your account, sign into Mapbox Studio and visit the [Tilesets](https://console.mapbox.com/studio/tilesets/) page.
> Example code:
**JavaScript**
```html
Add a vector tile source
```
**React**
```jsx
import React, { useEffect, useRef } from 'react';
import * as mapboxgl from 'mapbox-gl/esm';
import 'mapbox-gl/dist/mapbox-gl.css';
const MapboxExample = () => {
const mapContainerRef = useRef();
const mapRef = useRef();
useEffect(() => {
mapRef.current = new mapboxgl.Map({
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
accessToken: 'YOUR_MAPBOX_ACCESS_TOKEN',
container: mapContainerRef.current,
style: 'mapbox://styles/mapbox/standard',
config: {
basemap: {
theme: 'monochrome'
}
},
zoom: 13,
center: [-122.447303, 37.753574]
});
mapRef.current.on('load', () => {
mapRef.current.addSource('mapbox-terrain', {
type: 'vector',
url: 'mapbox://mapbox.mapbox-terrain-v2'
});
mapRef.current.addLayer({
id: 'terrain-data',
type: 'line',
source: 'mapbox-terrain',
'source-layer': 'contour',
layout: {
'line-join': 'round',
'line-cap': 'round'
},
paint: {
'line-color': '#ff69b4',
'line-width': 1
},
slot: 'middle' // middle slot in Mapbox Standard style
});
});
return () => mapRef.current.remove();
}, []);
return ;
};
export default MapboxExample;
```