This deal has expired, but be sure to check out our Top 25 deals of the week for savings on trips to destinations around the globe.

Are you an adventurous, spur-of-the-moment traveler looking for a great deal? For a four-day period, Quark Expeditions is offering passengers who buy one of four cruises to Antarctica in November at regular price (beginning at $6,190) an additional ticket for a companion for only $1. If you’re cruising solo, rates for these upcoming trips are 50 percent off.

Cruises to Antarctica are notoriously expensive, so this is a great deal if you’re able to jet to Ushuaia, Argentina, where the cruise departs, in the next week or two. This 12-day polar cruise travels through the Drake Passage, Antarctic Peninsula, and South Shetland Islands and offers a slew of adventurous activities, like kayaking, camping, mountaineering, cross-country skiing, and snowshoeing. Passengers will spot a variety of penguins and seals while marveling at the “big ice.”

The sale begins today at 8:30am and ends on Thursday, November 10 at 8:00pm; departure dates include November 13 (two sailings), 19, and 29, 2011.

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