Peaks high enough to thrill the climber with ambitions

JEBEL TOUBKAL, Morocco Starting out of the picturesque hillside village of Imlil, 40 miles from Marrakech, determined climbers can be up and down North Africa’s highest mountain in a weekend. A long first day will get you to the Refuge du Toubkal (3,200 meters), effectively denoting base camp, where you can catch some oxygen-deprived sleep before setting off for the top in the early hours. The twilight trudge over year-round snow is amply rewarded on the summit plateau, where there are spectacular views of the High Atlas buttresses tapering down toward the western shores of the Sahara Desert. Descend fast enough, and you can be back amidst the mayhem of the Marrakech souqs that same afternoon. Atlas & Sahara Tours (www.atlasandsaharatours.com) offers a two-day climb, including all transfers to and from Marrakech, for around $173 per person.

MAUNA LOA and MAUNA KEA, Hawaii With a combined volume enough to fill up the Grand Canyon 25 times over, these are the largest mountains in the world. Measured from the ocean floor up, they’re the tallest too, with Mauna Kea trumping Mount Everest by over 4,000 feet. Dramatic as the dimensions may be, however, they don’t present the most daunting mountaineering challenge. Defined as “shield volcanoes,’’ owing to their shallow profile, the gentle slopes offer a range of fair-weather trekking options, from one-day summit hikes to the 43-mile Mauna Loa Trail, which encompasses a four-day round trip over endless plains of rust-colored lava. Both mountains can be climbed without guides. Visit the Volcanoes National Park website (www.nps.gov/havo/planyourvisit) for information on trails and accessibility.