A travel writer shares how a trip to Antarctica helped him see that continent through the eyes of the early polar explorers. Then a reporter focused on climate change and conservation explains how some North American tree species are migrating to survive the planet's rising temperatures. And two Italy-based tour guides take us to the resort lakes of northern Italy, where the glamour extends beyond the natural scenery.

Learn about the customs that Greeks observe as Orthodox Easter draws near. Then contemplate the massive undertaking of building a cathedral centuries ago and how these monuments to faith and devotion helped shape their locales. And get acquainted with southern Spain's elaborate Semana Santa observances, which fill the streets of Andalucía in the week leading up to Easter.

Hear from tour guides about Spain's robust high-speed rail network and all the places it can take you. Then hit the road vicariously with Pulitzer Prize-winning journalist Nicholas Kristof for a taste of life as a foreign correspondent. And take a closer look at the surprising and fascinating ways in which borders have shaped our world.

Rick marks 20 years of his radio show by revisiting some memorable guests and what they've taught us about travel. Then author Paul Theroux celebrates his 84th birthday as he contemplates the passage of time in his new short-story collection, "The Vanishing Point." And actor Martin Sheen describes how his experiences filming overseas have come to influence his political activism.

Europe brims with world-class art, and we contemplate some of the continent's truly outstanding paintings, sculptures, and historic edifices. Then we learn about the historic and ecological importance of the Gulf of Mexico from a professor in neighboring Florida. And we consider the humble guidebook and what its pages can tell us, both in the moment and long after the trip is done.

A tour guide from Greece delves into the importance of food, family, and traditions in his homeland. Then a Francophile offers advice on how to take on the vast collection of the world's largest — and arguably greatest — museum. And guidebook researcher Cameron Hewitt shares discoveries from his travels in the Balkans, an affordable and rewarding alternative to the tourist crowds of western Europe.

Two countrymen explore Ireland's reverence for their national poet, W. B. Yeats. Then a Dublin journalist shares what it was like to grow up amid the turbulent societal changes in his city during the 1960s and '70s. And a guide from Belfast tells us why an Emerald Isle itinerary should include a visit to Northern Ireland.

Delve into the remote outposts and refuges across the globe where travelers have stopped along the course of their adventures. Then hear about the highest views in Wales — and how to reach them — and learn about the country's slate mining heritage. And from Alps to caves, vineyards to beehives, catch the buzz of the natural wonders on display in Slovenia.

Look at what's behind Carnival and Mardi Gras celebrations around the world by learning about the festive season's origins and customs in Germany's Rhineland. Then hear what's been added to the World Monuments Fund's latest "watch list" of endangered cultural sites around the world. And get recommendations for must-see experiences in Alaska, along with tips for planning adventures across the Last Frontier.

Two English tour guides explain what Brits mean by a "rough and ready" pub and how to find some of the UK's best pub grub. Then a father-and-son tour-guiding duo invite us to fall in love with their favorite corner of France. And BBC journalist Eliot Stein shares insights from his travels in search of the world's oldest disappearing traditions, giving us a peek into what it's like to be the last to carry a cultural torch.