Velebit caves
The "Lukina jama" cave is 1431 m deep (2013), the deepest cave in Croatia, 14th deepest cave in the world and the deepest cave in southeast Europe. At its foot, there are ponds and streams including one of the largest known colonies of subterranean leeches ("Erpobdella mestrovi"), which has been ascertained to represent a new species, genus and also family. Other species discovered in the system, include the air-breathing land snails "Zospeum tholussum". Like Lukina jama, Slovacka jama, Velebita and Meduza are also located at the "Hajdučki i Rožanski kukovi" special reserve, a dedicated part of the Sjeverni Velebit national park.
Yarlung Tsangpo Grand Canyon
The Yarlung Tsangpo Grand Canyon or Yarlung Zangbo Grand Canyon () or simply the Tsangpo Canyon, Brahmaputra Canyon or Tsangpo Gorge, along the Yarlung Tsangpo River in Tibet Autonomous Region, China, is the deepest canyon in the world, and at 504.6 km (314 miles) is slightly longer than the Grand Canyon in the United States, making it one of the world's largest. The Yarlung Tsangpo (Tibetan name for the upper course of the Brahmaputra) originates near Mount Kailash and runs east for about 1700 km, draining a northern section of the Himalayas before it enters the gorge just downstream of Pei, Tibet near the settlement of Zhibe. The canyon has a length of about 240 km (150 miles) as the gorge bends around Mount Namcha Barwa (7782 m) and cuts its way through the eastern Himalayan range. Its waters drop from about 2,900 m near Pei to about 1,500 m at the end of the Upper Gorge where the Po Tsangpo River enters. The river continues through the Lower Gorge to the Indian border at an elevation of 660 m. The river then enters Arunachal Pradesh and eventually becomes the Brahmaputra.