Gear review: Rab Mythic Alpine Down

About the product

The RAB Mythic Alpine Jacket is built to provide maximum warmth with minimal weight. The jacket is insulated with high-quality, 900-fill power ethically sourced goose down, ensuring superior warmth retention while keeping the jacket lightweight. RAB also applies their proprietary Nikwax® Hydrophobic Down treatment, which helps maintain insulation performance even in damp conditions by repelling moisture.

The outer fabric is Pertex® Quantum, known for being ultra-lightweight yet durable, providing wind resistance and packability. Weighing only 313 grams, the Mythic Alpine Jacket is easy to stow in a backpack without adding significant weight or bulk, making it ideal for fast-paced alpine climbs.

Technical features include a helmet-compatible hood with a stiffened peak, ensuring full coverage during cold, windy conditions. The harness-compatible hand pockets are designed for easy access while wearing a climbing harness, and the two-way front YKK zipper provides flexibility during ascents.

The jacket also incorporates zoned baffling, with larger baffles in the core for warmth and smaller ones in areas that need increased mobility. This ensures a balance between insulation and freedom of movement, ideal for climbers tackling technical routes or exposed ridgelines in cold conditions.

Tested

This summer, Deen tested the RAB Mythic Alpine Jacket during several high-altitude mountaineering expeditions under the guidance of mountain guide Jelle Staleman. The first test was the ascent of Grossglockner, Austria’s highest peak. In the chilly pre-dawn hours and at higher elevations, the Mythic Alpine Jacket’s 900-fill power-down insulation became essential. Its lightweight, packable design allowed Deen to stow it easily when temperatures rose, but when exposed to freezing winds and fog near the summit, the jacket gave him exceptional warmth.

Next, Deen took the jacket on the Chamonix beginner’s alpine course. The Mythic Alpine Jacket performed well during cold early mornings and high-altitude climbs. The hydrophobic down treatment meant that the insulation remained effective even in damp conditions. On days with, for example, light snowfall, the jacket’s Pertex® Quantum fabric kept the wind at bay, allowing him to stay comfortable while learning alpine skills on glaciers and rocky terrain.

The jacket faced another challenging environment on the Gran Paradiso ascent, where high-altitude glacier travel meant he needed effective insulation against the cold. Deen found that the Mythic Alpine Jacket struck a good balance between warmth and freedom of movement, thanks to its lightweight design. The zoned baffling provided warmth where it was needed most while allowing mobility in more technical sections of the climb. As temperatures dropped higher up on the glacier, the jacket’s helmet-compatible hood and adjustable fit made it easy to keep warm without restricting movement.

The Mythic Alpine Jacket’s ultimate test came during the Monte Rosa 7 summits expedition, a multi-day trek across some of the highest peaks in the Alps. The jacket needed to handle a variety of conditions, from the cold and wind at higher altitudes to warmer temperatures during the descents. On exposed ridgelines and at higher huts, where winds and low temperatures were a constant challenge, the jacket’s combination of lightweight construction and high warmth retention made a noticeable difference. The jacket’s harness-friendly design allowed Deen to access his pockets and camera gear quickly, without the need to adjust or remove layers.

One of the standout features during these expeditions was the Mythic Alpine Jacket’s ability to maintain warmth in damp conditions. During mountaineering trips there can be unpredictable weather, including fog and light precipitation, the hydrophobic down proved crucial in ensuring the jacket didn’t lose loft or warmth, even in less-than-ideal conditions. Despite being lightweight, the jacket’s warmth and compactness made it an essential part of Deen’s layering system throughout the expedition.

Across all these mountaineering tours, the Mythic Alpine Jacket was a key piece of gear. Its balance of warmth, weight, and packability ensured that Deen stayed comfortable in changing conditions, while its technical features, such as the harness-compatible pockets and helmet-compatible hood, made it a practical choice for multi-day climbs and high-altitude adventures.