Perfect for high-altitude mountaineering and glacier crossings: the Beal Rando Golden Dry 8mm. Both the core and the sheath have been treated. This reduces the rope's water absorption in wet conditions, keeping it below 3%. This far exceeds the UIAA Water Repellent Standard. With an 8mm diameter and only 37 grams per metre, it'll hardly take up any room in your pack, but it will provide the protection you need in the event of a fall.
Important:Beal recommends using one strand of a twin rope for roping a party. Using one strand of the Rando for activities like mountaineering or climbing is strictly prohibited. Only the use of both strands can provide the necessary safety in the event of a fall.