Guardian India correspondent Michael Safi takes a journey along the Yamuna river. Subscribe to The Guardian on YouTube ► http://is.gd/subscribeguardian Stretching 855 miles (1,375km) across the north of the country, at its source in the Himalayas its water is crystal clear. However, once it streams through New Delhi, it turns into one of the filthiest rivers in the world. Rapid urbanisation is partly to blame, but so is lax enforcement of laws against illegal dumping. Support the Guardian ► https://support.theguardian.com/contribute Today in Focus podcast ► https://www.theguardian.com/news/series/todayinfocus Sign up for the Guardian documentaries newsletter ► https://www.theguardian.com/info/2016/sep/02/sign-up-for-the-guardian-documentaries-update The Guardian ► https://www.theguardian.com/ The Guardian YouTube network: Guardian News ► null Guardian Football ► null Guardian Sport ► null Guardian Live ► null #yamuna #india #pollution #himalayas #delhi