A History Written in Altitude.

Thamserku is founded in Kathmandu as a Sherpa-led expedition company and moves immediately to the technical end of the range. Within its first decade, the company organises the fastest Everest ascent yet recorded (Batard, 1988), the first Nepali woman's summit of Everest (Pasang Lhamu Sherpa, 1993), and Hans Kammerlander's ski descent from the summit of Everest (1996), while establishing operations on Dhaulagiri, Pumori, Ama Dablam, Baruntse, and Cho Oyu. By the close of its founding decade, Thamserku has built the operational vocabulary that the next thirty years of Himalayan expeditions will largely be conducted in.

Thamserku becomes one of the most active expedition operators in Nepal. Cho Oyu grows into the largest single operation in the company's history, with 217 expeditions organised across the decade as Manaslu, Everest, and other exploration programmes run in parallel across the country's ranges. Notable milestones include the Nepali Everest speed landmark of 1998, Jean-Christophe Lafaille's solo ascent of Manaslu in 2000, Temba Tsheri's record as the youngest summiteer in 2001, first ascents to Tripura Hiunchuli 2 (3,400m) in 1993 and first new route ascent to Manaslu South-East in 2004. The decade closes at full strength, with 78 expeditions coordinated in 2006 alone.

Commercial mountaineering transforms across the decade — fixed-rope consortiums consolidate the workhorse routes, modern forecasting reshapes how weather windows are read, and helicopter logistics rewrite the rhythm of Base Camp operations on every major peak. Thamserku operates through every shift, absorbing the systems knowledge that now underpins its safety architecture and adapting its ground model without losing the standard the founding decade established. Each advancement has been tested, integrated, and held against the company's own institutional memory of how Nepal's mountains actually behave.

In 2020, Thamserku steps back from active operations in a deliberate dormancy through the pandemic years and the industry upheaval that followed. The decision is structural rather than reactive: a recognition that the standards built across three decades cannot be carried through a market in deep and prolonged flux without compromise. The pause is held intact, the institutional knowledge preserved within the wider Yeti Group, and the operating record kept rather than diluted — the rarest decision an expedition company of this standing has made: to stop, deliberately, and wait for the ground to return on.

In 2026, Thamserku returns under a new generation of leadership, backed by the Yeti Group's aviation, hospitality, and ground infrastructure, with a portfolio of thirteen peaks chosen with purpose rather than simply accumulated over time. The return is a reconstruction rather than a restart: every expedition supported by an integrated foundation built across decades, and the operational standard of the original company carried forward into a new era. The record stands, and Thamserku now adds to it. The 2026 season is led by expeditions to Everest, Lhotse, Ama Dablam, Manaslu, and the full Atlas of peaks.