The Argentière Glacier is a magnificent hulk of ice. At nine kilometers long (5.6 miles), it’s one of the largest glaciers in France’s Mont Blanc massif, though like most glaciers across the globe, it has been shrinking at a steady pace. Satellite images from various years give a birds’ eye view of the great river of ice retreating further into the mountains.

For now, with just a 30-minute bus ride from downtown Chamonix, two chair lifts, and a two-hour hike, you’ll be standing right at the glacier’s edge. The glacier is named for the nearby village of Argentière.

You can access the glacier itself via the Albert Premier Hut, which looks right out onto the mass of packed ice. For a day hike, amble over there for lunch on their glacier-side patio, where supplies must be delivered by helicopter. Or, if you want to take things a step further, hire a guide through a local agency, spend the night in one of the bunk rooms, and trek out on the glacier itself, outfitted in ropes, helmet, and crampons.

You’ll leave by 6am in order to summit the glacier before the sun starts to really warm things up. The Argentière Glacier by moonlight is a magnificent sight—twinkling different shades of blue and white. Towards the top of the glacier, you can sit right on the rocky ridge bordering both France and Switzerland, looking out over the seemingly endless sea of ice. The ridge stands at a bit above 2,300 meters, or 7546 feet.

Enjoy the view. You may be among the last generations to see it.