Gear Review: Mammut Mercury Advanced GTX Heavy Duty Boots

You'd never expect this model's protection by looking at it's ultralight weight.

[best weight-to-protection ratio] 

The Mercury Advanced carves out its own class of boot: the light heavyweight. “At two and a half pounds, it’s slightly heavier than a light hiker or approach shoe, but far more protective of ankles, with better padding and weatherproofing,” reports a Utah-based climbing guide who pushed the Mercury to its limit, carrying up to 40 pounds off-trail on slickrock and loose talus in Capitol Reef National Park in temps dipping to 0°F. The key to the low weight is minimalist armor. Instead of using heavy rubber rands, Mammut applies thin rubber toecaps, which proved very durable. While hiking 37 miles within three days of unboxing them, our tester experienced no hot spots and found the boots supple and cushy enough for long days, thanks to a snug heel cup and midfoot section, plus a high-volume toebox that allows for long-mileage swelling and foot squish under loads.

The high-cut, Gore-Tex-lined Mercury boasts superior traction as well; credit scale-like lugs on the outsole, beveled at a low angle facing the front of the shoe and angled up sharply on the rearward side for extra bite on climbs. “And thanks to their high-volume heel block, these Mammuts have a notably soft footstrike, even on bedrock,” our tester says. “It’s remarkable to me how these boots provided support—in the ankle and underfoot—and a snug fit without being overly stiff like other board-lasted boots I’ve worn. They felt like they were poured around my typically hard-to-fit, wide feet.” Best for hikers with average to wide, high-volume feet looking for ankle support, forefoot room, and a soft, easy stride for day- to weeklong trips. Bonus: great price for the performance. $189; 2 lbs. 8 oz. (m’s 9.5); m’s 6.5-13;