Punta Arenas' airport (PUQ) is 21km north of town.
Aerovías DAP offers Antarctica tours (full day US$5500), charter flights over Cabo de Hornos and to other Patagonian destinations, including Ushuaia and El Calafate, Argentina. From November to March, flights run to Porvenir (CH$55,000 round-trip) Monday through Saturday several times daily, to Pampa Guanaco in Tierra del Fuego, and to Puerto Williams (CH$143,000 round-trip) Monday through Saturday at 10am. Luggage is limited to 10kg per person.
Transbordador Austral Broom operates three ferries to Tierra del Fuego. The car and passenger ferry to/from Porvenir (CH$6200/39,800 per person/vehicle, 2½ to four hours) usually leaves at 9am but has some afternoon departures; check the current online schedule. From Punta Arenas, it's faster to do the Primera Angostura crossing (CH$1700/15,000 per person/vehicle, 20 minutes), northeast of Punta Arenas, which sails every 90 minutes between 8:30am and 11:45pm. Broom sets sail for Isla Navarino's Puerto Williams (reclining seat/bunk CH$108,000/151,000 including meals, 30 hours) three or four times per month on Thursday only, returning Saturday.
Buses depart from company offices, most within a block or two of Av Colón. Buy tickets several hours (if not days) in advance. The Central de Pasajeros is the closest thing to a central booking office.
For Chile's Lake District, try Cruz del Sur.
Daily destinations and companies include the following: Punta Arenas