Routes can vary depending on weather conditions in this notoriously capricious climate. After an evening departure from Punta Arenas ’s Muelle Prat, the vessel crosses the Strait of Magellan to enter the Seno del Almirantazgo (Admiralty Sound), a westward maritime extension of the freshwater Lago Fagnano  trough.
Passengers usually go ashore at Bahía Ainsworth, near the Glaciar Marinelli, where there’s a short hiking trail through what was once forest until feral beavers dammed the area into a series of ponds; the most interesting site is a small elephant seal colony. Farther west, at Isla Tucker, there’s a Magellanic penguin colony (usually observed from an inflatable Zodiac) and it’s also possible to see the rare striated caracara (Phalcoboenus australis).
After a night’s sailing, the ship may enter the Fiordo D’Agostini, a glacial inlet named for the early-20th-century Italian priest and mountaineer who explored the Cordillera Darwin’s farthest recesses. When high winds make it impossible to approach the Glaciar Serrano (named for Chilean naval Lieutenant Ramón Serrano Montaner, who charted the Strait in 1879), an option is the more sheltered Glaciar D’Agostini. Even here, though, seracs crack off the glacier’s face, touching off a rapid surge of water and ice that runs parallel to a broad gravel beach and, when it subsides, leaves the beach littered with boulders of ice.
After navigating Canal Cockburn, where open ocean swells can rock the boat at least briefly, the vessel turns into the calmer Canal Ocasión and eventually enters the Beagle Channel’s north arm, sailing past the so-called Avenida de los Glaciares, a series of glaciers named for various European countries; passengers normally disembark at Glaciar Pía, where dozens of waterfalls cascade down sheer metamorphic slopes from the glacier and passengers take a short hike.
Weather permitting, the ship sails south to Cabo de Hornos (Cape Horn) and, wind permitting (less than 45 knots), passengers disembark to visit the small Chilean naval detachment and hike to the stylized albatross sculpture that symbolizes sailors who lost their lives “rounding the Horn.”
On occasion, the captain can choose to round the Horn himself before proceeding north to Bahía Wulaia, on Isla Navarino’s western shore. Here passengers visit the site of an early mission where, in a notorious incident, the Yámana massacred all but one of the Anglicans and their crew. There is then the option of a short but steep hike with panoramic views of the bay, or an easier shoreline walk to see birdlife that includes Magellanic oystercatchers.
Northbound, emigration formalities now take place at Puerto Navarino, at the western end of Isla Navarino. Proceeding to Ushuaia, all passengers spend the night aboard; those returning to Punta Arenas have the day free in Ushuaia before returning to the ship, while new passengers check their bags downtown before boarding in late afternoon.
After reentering Chile at Puerto Navarino, the ship sails south to Wulaia and Cabo de Hornos and then, returning to the Beagle Channel, the ship veers westward through the Beagle Channel’s north arm, again passing the Avenida de los Glaciares and entering Fiordo Pía. Proceeding through the afternoon and the night, the boat starts the last full day navigating the Fiordo Chico (Little Fjord), where passengers board Zodiacs to approach but not land at Glaciar Plüschow, named for a German pioneer aviator who took the first aerial photos of the Cordillera Darwin.
In the afternoon, the Glaciar Águila is the site of an easy shoreline walk or a more demanding slog through knee-deep mud in a southern beech forest (the video footage of this hike, shown the night before in an orientation session, is priceless). On the final morning, the boat sails north to Isla Magdalena  before returning to Punta Arenas .