Patagonia, Argentina: Puerto Madryn, Punta Tombo, Rawson, Gaiman, Bryn Gwyn National Park and Trelew

There is a Gaelic proverb that says, "The sea wants to be visited," and I believe that wholeheartedly. It calls to us and sets our minds racing. The world's oceans have driven men mad; either you crave it desperately or it maddens you if you are out too long. There is middle ground, however, and I believe it is found on the coastlines. Beaches, breaks, reaches, spits, sand and surf. Paradise for some, respite for others. The coast can be a starting point for a journey or a place to land and call home. It calls to us here on the National Geographic Endeavour, and we continually visit the sea.

Crystal-clear morning light accompanied us to the legendary Magellanic penguin colony at Punta Tombo. Half a million pairs of penguins come here to dig out a burrow, court, and mate, lay eggs and raise little fluffy penguin chicks. From aqua-colored waters that bathe the coastline and as far as the eye can see there are penguins, guanacos, armadillos, maras, rheas and myriads of shorebirds. The adult penguins stand at attention protecting their chick from the sun, the wind, or perhaps a Patagonian fox as well as from the avian thieves - the gulls and the skuas.

Researchers here are studying all aspects of the penguin's natural history; the threats and changes to the populations, as well as biological data such as mate fidelity and chick survivability. Five years ago I was lucky enough to be able to come here and volunteer some time as a penguin biologist, and I got to handle the feisty critters, weighing and measuring their chicks, checking their overall condition. It was magic.

Others in our group were just as mesmerized as they visited a fossil quarry and then an outstanding museum in the quaint town of Trelew. Huge dinosaurs are displayed there, many analogous to the North American biggies like the T-Rex and the brontosaurus. They also had a proper Welsh tea in the town of Gaiman, settled several generations ago.

We end our epic voyage today after traveling far and wide - some of us all the way across the Atlantic from Lisbon and on down the coast of eastern South America.

In "Travels With Charlie." John Steinbeck wrote, "Once a journey is designed, equipped and put in progress; a new factor enters and takes over. A trip, a safari, an exploration, is an entity, different from all other journeys. It has personality, temperament, individuality, uniqueness. A journey is a person in itself; no two are alike. And in all plans, safeguards, policing, and coercion are fruitless. We find after years of struggle that we do not take a trip; a trip takes us."

And so it goes.