Tirthan valley is named after a sacred water spring "TIRTH" The spring is the origin of Tirthan stream and water is adored as sanctifying as that of legendry Ganga river .The valley begains its domain from Largi , the place where Tirthan and Sainj streams merge with Biyas river . Dam at Largi holds the water of these three rivers .
The valley is glorified and beautified by perennial alpine trees and lush green pastures. And to top it all ,Tirthan stream abounds in trout fish and is globally renowned for angling. British rulers identified Tirthan water, crystal clean as it is , most suitable for trout fish They brought seeds of best quality fish from SCANDANAVIAN countries and put them in the Tirthan stream to thrive.
Tirthan Valley lies on the banks of River Tirthan. The area is known for the Trout fishing and access to Great Himalayan National Park (GHNP). Tirthan Valley Area is green and good for trekking, overnight camping, river crossing and all kinds of adventure activities.
In June 2014, the Great Himalayan National Park was added to the UNESCO list of World Heritage Sites.[1]The Unesco World Heritage Site Committee granted the status to the park under the criteria of "outstanding significance for biodiversity conservation.
The GHNP is at the junction of world's two major faunal regions: the oriental to the south and palaearctic to the north. The temperate forest flora-fauna of GHNP represents the western most extension of the Sino-Japanese Region. The high altitude ecosystem of the Northwest Himalaya has common plant elements with the adjacent Western and Central Asiatic region. As a result of its 4,100 m elevation range the park has a diversity of zones with their representative flora and fauna, such as alpine, glacial, temperate, and sub tropical forests.