lbishorn creates vintage watches that never existed, yet could have. This approach, defined as “Imaginary Vintage^®”, explores untold paths in horological history.

Each timepiece is conceived as a missing link—one that integrates seamlessly into the established canon while asserting a character of its own.

With the Thundergraph Khumbu, Albishorn revisits a singular question: what form might an alpine chronograph, hypothetically designed for the Swiss Everest expedition of 1952, have taken?

To answer it, we return to that pivotal year—retracing the imagined origins of the Thundergraph, a chronograph conceived as a lost chapter in the evolution of exploration timepieces.

On May 29, 1953, Sir Edmund Hillary and Tenzing Norgay reached the summit of Mount Everest, marking a defining achievement in mountaineering history. Yet it was the Swiss, renowned for their climbing expertise, who first pursued this objective.

In 1952, the Swiss Foundation for Alpine Research organized two expeditions to Mount Everest under the direction of Dr. Edouard Wyss-Dunant. Nepal had just opened its borders to foreign climbers, and the Swiss were among the first to receive permission. The expeditions brought together leading Swiss mountaineers and Tenzing Norgay, whose experience proved decisive for his later success with Hillary.

The spring expedition (pre-monsoon) was particularly significant. Raymond Lambert and Tenzing Norgay reached 8,600 meters—the highest altitude ever achieved at the time— just 250 meters below the summit.

Exhaustion, lack of oxygen, and worsening weather forced them to turn back, but their attempt confirmed the viability of the Southeast Ridge route.

The 1952 Swiss expeditions remain a landmark in mountaineering history, defined by technical mastery, collaboration, and a measured approach to risk.

Albishorn set out to imagine the tool-watch that could have accompanied such an expedition—a chronograph designed to support climbers throughout their ascent in the harsh conditions of the Himalayas. The result captures both the pioneering spirit of exploration and the functional relevance of a wrist-worn chronograph.

The mission was to envision a chronograph tailored for Himalayan exploration—a reliable instrument to track time and manage progression in unforgiving conditions. Legibility and functionality in extreme cold and low-light environments were central to the design. The dial features bold Roman numerals and luminescent hands, ensuring optimal readability in darkness or storms. Ease of use is equally critical: the oversized bezel, robust crown, and prominent red monopusher are designed for operation even with thick gloves.

The chronograph complication, combined with the rotating bezel, allows climbers to precisely time ascent phases, rest intervals, and other critical activities—making it an essential tool in extreme environments.

The Thundergraph Khumbu introduces a green dial, inspired by the landscapes of the Khumbu region, where ice, rock, and sparse vegetation coexist under extreme conditions.

It retains the legible Roman numerals and triangular indexes of the original design, ensuring optimal visibility in low-light situations. The luminescent hands support reliable timekeeping during nighttime expeditions.

The running seconds and 30-minute counters are positioned at the bottom of the dial, preserving space for the four cardinal indexes. The dial, nicknamed “California ghost,” offers a minimalist interpretation of the traditional California layout.

While the classic California dial combines Roman and Arabic numerals, this version omits Arabic numerals entirely. The upper half features gilt Roman numerals, while the lower half is dedicated to two subdials. This approach balances heritage aesthetics with functional clarity.

The case is crafted from high-grade stainless steel, selected for durability and resistance to extreme conditions. Its construction ensures reliability under impact and temperature variation. With a height of 12 mm (including the sapphire box crystal), the Thundergraph remains notably slim while maintaining a strong presence. Brushed and polished surfaces create a balance between robustness and refinement.

The crown, positioned at 10:30, improves ergonomics and allows winding without removing the watch. This asymmetrical placement also contributes to the watch’s distinct identity.

Available in steel or bronze, the crown emphasizes the tool character of the watch. The bronze version develops a natural patina over time, adding visual depth.

The large single pusher at 9:30 ensures intuitive chronograph operation, even in demanding conditions. Its placement prioritizes accessibility and ease of use.

The oversized rotating bezel enhances functionality. Its conical profile adds depth while improving grip, and the knurled edge allows precise handling in challenging environments.

The case back features an engraving of a Swiss cross and rope, referencing the emblem of the Swiss Foundation for Alpine Research.

The Thundergraph is powered by a proprietary hand-wound mechanical chronograph movement, certified by the COSC. Manufactured in La Chaux-de-Fonds, it delivers precise timekeeping and reliable performance, with a power reserve of 65 hours.

The movement was developed to accommodate the distinctive dial layout, with subdials positioned at 4:30 and 7:30. Its height of 5.70 mm enables a slim chronograph profile reminiscent of 1950s designs.

The monopusher configuration at 9:30 allows for intuitive control of the chronograph. This approach reflects early chronograph constructions and reinforces the watch’s functional clarity.

The Thundergraph Khumbu is delivered with two straps: a beige leather strap and a black leather strap, both fitted with an Albishorn buckle.

In addition, it is available with a stainless steel bracelet. Its design draws from traditional “bamboo” bracelets, reinterpreted in a more technical construction. Each link is secured by screws, allowing full adjustability.

Two discreet extension systems are integrated on each side of the bracelet, enabling quick adjustment directly on the wrist without removing the watch.

The Thundergraph Khumbu is priced at CHF 3,650 on a leather strap, with two straps included, excluding taxes, tariffs and shipping. The version on the steel bracelet, also supplied with two additional leather straps, is priced at CHF 4,100, excluding taxes, tariffs and shipping. Limited to 99 pieces (unnumbered), produced over a period of three years, it is available exclusively online at www.albishorn-watches.ch.

TECHNICAL SPECIFICATIONS

Dial

• Mint green opaline dial with golden applied indexes filled with beige Super-LumiNova®

Hands

• Brushed golden hour, minute and second hands filled with beige Super-LumiNova® Red chronograph second and minute hands filled with beige Super-LumiNova®

Case

• 316L stainless steel case with polished and satin finished surfaces and with chamfered and polished edges
• Case diameter: 39 mm
• Lug to lug: 47,7 mm
• Lug width: 20 mm
• Case thickness: 12 mm (with sapphire); 11.1 mm (without sapphire)

Bezel

• Bidirectional rotating stainless steel bezel with engraved and lacquered back and red figures and indexes
• 60 units scale
• Bezel diameter: 42.7 mm
• Winding Crown and pusher
• Bronze winding crown with engraved Albishorn logo Pusher in red anodized aluminum

Crystal

• Box sapphire crystal with antireflexive coating
• Waterproofness
• Waterproof to 100 meters

Movement

• Proprietary chronograph caliber ALB03 M
• COSC certified chronometer (Contrôle Official Suisse des Chronomètres)
• Manual winding
• Monopusher
• Height: 5,70 mm
• Diameter: 30,00 mm
• Hours and minutes
• Running seconds at 4:30 o’clock
• 60-second counter in the center
• 30-minute counter at 7.30 o’clock
• Stop second device
• 28’800 vibrations per hour (4 Hz)
• 21 jewels
• Typical power reserve: 65 hours

Straps

• Black leather strap with Albishorn buckle Beige Leather strap with Albishorn buckle Bracelet (optional)
• Steel bracelet with individually screwed links, a double-folding clasp featuring the Albishorn logo, two concealed extensions (one on each side), and a quick-release system.