This impossibly blue lake with crystal clear water is one of Indonesia's hidden gems. Video shows the journey to reach the Kali Biru lake, located on the island of Waigeo, Raja Ampat, in the West Papua region of the country. Travellers must trek across land and sea to reach the remote island, which is largely untouched by foreign tourists but popular with locals. The distance of the journey means travellers must pay 500,000 Rupiah (£25) to reach its shimmering waters.But once there, it's worth it. The video was captured on April 8.