Mountaineering activities of Chanchal Mitra, who belonged to Kolkata, spanned more than six decades. His biggest achievement was to successfully lead the Himalayan Association-organised expedition to 23,210 feet Tirsuli in Kumaun Himalaya in 1966. It was the first ever ascent of the peak.

 

Mitra's love for the mountaineering began when he visited Darjeeling as a school student. His passion for climbing intensified after a trek to Gangotri and Yomunotri. He subsequently took his basic and advance mountaineering training at HMI Darjeeling.

 

Beside Tirsuli, Chanchal Mitra, also participated in the Nilgiri Parvat expedition of the Himalayan Association which made the first Indian ascent of the peak in 1962. He also led Herdeol Expedition in 1967 and the first expedition of the National Cadet Corps (NCC) in India to Panchachulli peaks in 1970. He participated in an expedition to Nitalthaur in Kumaun Himalaya in 1974.

 

In 1976, while on a trek from Gaumukh to Badrinath via Kalindi Khal, Mitra, along with then-instructor of NIM Uttarkashi, Harsmuni Nautiyal, made the first ascent of an unnamed peak of about 20,000 feet in Kalindi Khal region.

 

He was one of the initiators of rock climbing training course in Eastern India at Sushunia Hills of Bankura district in West Bengal which was organised by Himalayan Association in 1965.

 

Chanchal Mitra was a life member of Himalayan Mountaineering Institute, Darjeeling, Himalayan Club and Kolkata-based Himalayan Association, where he also served as its president and secretary. He also acted as editor of first two issues of Himalayan Association Journal.