BROWN BLUFF, Antarctica (AP) -- Stepping carefully down the cruise ship's gangway, I wait for a break in the swelling waves to make my move.

With a quick stride, I settle on to a small rubber boat. Within minutes, our small group of tourists bounces by floating chunks of strikingly blue ice and a napping seal. The boat lands on a rocky beach, and I swing my legs over the Zodiac to step on the northern tip of the Antarctic Peninsula.

Walking by blocks of beached ice, my senses are struck by a tremendous sight and a pungent guano smell. Hundreds of adelie penguins are waddling around in front of me. Their numbers stretch high up a rocky slope, about as far as I can see.

It's our first landing on this remotest of continents, and already the two-day cruise from Ushuaia, Argentina, through infamously rough seas is paying off. Increasingly, travelers worldwide are realizing this vast crystalline wilderness at the bottom of the world is well worth the trouble to visit. Some 26,000 visited in the past year, and the number increases annually.

"Each year seems to be the highest ever," says Kara Weller, who is leading this trip for Quark Expeditions.

It may be the coldest continent in the world, but the weather can be surprisingly pleasant during the December days of the austral summer. Temperatures often get above freezing -- even into the 40s on the peninsula. Trips usually run from November to March.

Most of this trip spanning 11 days is spent at sea on the M/V Orlova, a 100-meter ice-strengthened cruise ship that is nearly full with about 100 passengers. The ship is comfortable, but not fancy. It has a bar and lounge with a small library and an auditorium. Small yachts also make trips to Antarctica. Much larger cruise ships also come down here.

Unforgettable experiences
We leave port on a Friday night. The next day, we're already able to watch the powerful glides and graceful arcs of wandering albatrosses and other birds of the southern seas.

To pass the time at sea, tour guides mix in numerous lectures by various experts, including a bird specialist, a marine biologist, a geologist, a historian -- even an artist who gives lessons on drawing and painting icebergs and penguins. Lectures on global warming are surprisingly absent on this trip, though, but Weller says the topic is usually discussed.

Many of the trip's highlights happened during landings on the continent and nearby islands.

Watching an avalanche from a distance or hearing the stentorian cracking boom of a calving iceberg are unforgettable experiences. Still, there is plenty to see from the ship's decks. With few hours of darkness this time of year, tourists are able to maximize sightseeing.

So long as you're heavily dressed to keep warm from strong winds, it's easy to spend a couple of hours on deck watching a large array of wind-carved icebergs floating by, some bright white, others various shades of blue. We pass pristine landscapes of high mountains laden with big hanging glaciers. Whales also rise up into view occasionally. Sunsets can be long-lasting, lighting up the sky with bright orange and reds.

We see hundreds more penguins on Aitcho Island. Gentoo penguin nests are clumped together, and they are hard at work using their beaks to steal small stones from each other to improve their nests. For the most part, the awkwardly sneaky penguins seem to break even amid the ruckus.

It's not long, though, before we get our first taste of the extremely fast-changing Antarctic weather. Strong winds and thick ice force us to cancel a landing at Paulet Island, home to thousands of adelie penguins.

The unpredictable nature of Antarctic weather was evident again several hours later, when our path to Devil Island was blocked by ice. Our ship had to turn around as we came across sheets of ice at sea. It's not so bad being stuck on the ship, though, with plenty of large tabular icebergs to watch at sea.

After yet another canceled landing at Half Moon Island the next day, we finally get a break in the weather and make it to Deception Island, a dormant volcano. As chinstrap penguins pop up and down in quick bursts beside the ship, we ease through a narrow opening called Neptune's Bellows and to a natural harbor known as Whaler's Bay.

A couple of hours later, we cruise up the island's caldera to Pendulum's Cove, where visitors can take a polar plunge in waters heated by the volcanic activity.

Penguin highways
The next morning, we land on Cuverville Island, where scores of gentoo penguins are sitting on eggs. Before heading back to the ship, we take a Zodiac cruise around a group of icebergs, giving us a close look into cavernous openings with swirling blue patterns.

After lunch, we visit Danco Island, with more breeding gentoo penguins. Here, they have worked out a network of well-worn "penguin highways," trails in the snow to aid climbs up a steep hill to other penguin groups. While waiting to get back to the ship, a couple of us spot a bright orange 10-legged spider-like creature floating between some rocks by the beach. Known as a sea spider, it would more than cover the palm of a hand. It's one of those unusual critters you can come across here.

Back on the ship, we get some alarming news that one of the older passengers is very sick and will need to be evacuated. This means we will make a long detour overnight and go back to the South Shetland Islands to get to an airstrip. Because of evacuations like this, which can cost tens of thousands of dollars, many tour groups highly recommend that passengers get medical evacuation insurance.

After the passenger was evacuated to Chile, we visited Ardley Island, where newly hatched gentoo penguins are being fed by their parents. An adult penguin delicately takes the chick's head into its mouth and regurgitates a snack of krill into the chick's mouth, leaving a slimy strand from beak to beak.

Then we dropped by research stations on a nearby island. One of them even has a gift shop. The area is the only eyesore on the trip, with rusting barrels and the smell of fuel in the air.

Trying to make up for some lost time, we head south again for a packed last day, hitting one of the trip's highlights at Paradise Bay. Mountains here are covered with glaciers, which press down in a still, jumbled bluish-white fury of ice.

At our farthest point south, we are still 1,487 nautical miles from the South Pole. The whole trip will be 2,268 nautical miles.

Before making the two-day trip back, we wrap up the visit in the Lemaire Channel, where the water creates mirror images of a long string of mountains on both sides of us.

A pod of orca whales swim quickly beside the ship, their black and white bodies submerged but visible through the clear water.