In November the predominately Irish expedition of Jack Bergin, Martin Boner, Kevin Higgins, Ursula McPherson, Keith Monaghan, Alan Tees (leader), Jimmy Tees, Thendup Sherpa, and I became the first group to complete the traverse of the Zumthul Phuk Chu gorge, reach the Zumthul Phuk Glacier, and carry out exploration.

This route was envisioned in 1891 by John Claude White, the first British political officer to Sikkim. Traveling to Lhonak via the Tulung Gompa, White had noted the large stream, which he referred to as the Zamtu Chu, emanating from the eastern flanks of beautiful Siniolchu (6,887m), and was tempted to follow it upward. In October 1931, after their daring attempt on Kangchenjunga, Eugen Allwein and Hans Pircher crossed from the Zemu Glacier via the Simvu Saddle to the Passanram (a.k.a. Passamram) Glacier, where they were struck by a prominent set of formations. This was probably the first documented sighting of the Siniolchu Rock Needles, which lie on the long south ridge of Siniolchu. They were followed by Paul Bauer's 1937 expedition, which attempted to cross the watershed between the Passanram and Zumthul Phuk glaciers. They reached a saddle to the southeast of the Rock Needles that they named Kukur La (ca 5,300m).

Since then no party had attempted to have a closer look at the Rock Needles, although in 2006 I managed to force a way up the Zamtu Chu gorge and reached the terminal moraines of the Zumthul Phuk Glacier. Bad weather prevented any view of the mountains. In 2009 I was back with Thendup Sherpa and got partway up the Zumthul Chu gorge, where we caught a clear view of the Rock Needles.

Our team arrived in Beh at the end of October. A walk of three short days took us to Talung. Then, with the help of porters who blazed a trail through the rhododendron forest with machetes, we reached a base camp at 3,800m, above the worst of the vegetation. Half an hour above camp lay a beautiful lake, and to the left the Siniolchu Rock Needles. A little later Alan Tees was forced to return to civilization due to a severe tooth abscess, but the rest of the group moved to an advanced base, from which they reconnoitered a route to a shoulder on the Rock Needles. The following details are taken from Martin Boner's diary.

The eventual route led up a gully (Scottish 3/4), on thin ice and névé, giving access to easier angled slopes. A high camp was established at 4,740m. The following day, three hours of hard labor led to the col above, from which there were magnificent views of Kanchenjunga, Talung, Kabru, and Pandim. It was decided to name this Brothers Tees Col (5,250m). Snow leopard tracks were visible.

The following day advanced base was moved to the other side of the moraine to give better access to the northern side of the Zumthul Valley. A second high camp was placed farther up, at 4,768m, and it was noted the upper valley was much wider than depicted on the map. The weather remained unsettled, but on the morning of November 13, which dawned with another covering of snow, the party climbed to a narrow opening on a sharp ridge, which they named Mari Col (5,046m). From there they discovered a massive intact glacier rising to Siniolchu’s east ridge, with a series of unclimbed peaks at its head. They ascended a small rock summit of 5,100m that they named One Hand Peak. Next day they descended to base camp, and on the following day made a tough seven-hour walk through mist and rhododendron down to Talung.

-Anindya Mukherjee, India