STONE FOREST OF CHINA: In Yunnan Province you'll find the famous limestone formation that looks like stalagmites, or petrified trees. Two sections have been designated UNESCO World Heritage Sites. The pillars are the biggest in the world, with a wider range of shapes and colors than anywhere else on Earth. Info: whc.unesco.org/en/list/1248
CAPPADOCIA, TURKEY: It's on my bucket list. Got as close as the spires of Istanbul, but gotta see those natural spires — "fairy chimney" rock formations — at Goreme National Park in Cappadocia, a history-rich region that also boasts complex underground cities and buildings carved right from the rocks, including churches and the traditional pigeon houses (pigeon excrement was used as fertilizer by farmers with nutrient-poor soil). Oh, and you too can sleep in traditional style, in a cave hotel. Info: goturkey.com/en
STONE FOREST OF MADAGASCAR: Tsingy de Bemaraha National Park. This park not only offers visitors a chance to see rare and unique species, but marvel at the way they survive and thrive in what is a stunning but almost impenetrable habitat of jagged limestone needles and canyons. Visitors can appreciate it, at least some of it, on treks, walking above the forest on hanging bridges. Info: madagascar-tourisme.com/en
SALAR DE UYUNI, ALTIPLANO, BOLIVIA: The world's largest salt flat on the Bolivian altiplano stretches over more than 4,633 square miles. You can even stay in a hotel made of salt. Info: bolivia.travel
GIANT'S CAUSEWAY, COUNTY ANTRIM, NORTHERN IRELAND: You can see how these impressive basalt columns leading down to the Atlantic Ocean got their name and inspired the legend that they were built by giants. nationaltrust.org.uk/giants-causeway
NAMIBIA: The wildlife alone — and the well-organized growth of tourism infrastructure — are reasons enough to put this country in southwestern Africa at the top of a bucket list. After you've looked a cheetah in the eye, however, you'll find some of nature's geological wonders as well. The country boasts a variety of extreme landscapes, the Namib Desert arguably the most jaw-dropping. In the central Sossusvlei region you'll find the 20,000-square-mile Namib-Naukluft National Park, boasting, at its heart, a surreal sweep of high, red sand dunes — a kind of Sahara through rose-colored glasses. You'll find more examples of extreme desert beauty in the northwestern area known as the Skeleton Coast, an environment so wild most of it is inaccessible. Info: namibiatourism.com.na
ARIZONA: Antelope Canyon, the oft-photographed, pink-and-peach-striped slot canyon on Navajo tribal lands, is but one of the wows in northern Arizona. To the northeast, you can drive a loop out of Flagstaff that includes the scorched scenery of sunset crater; Wukoki and Wupatki Indian ruins overlooking the Painted Desert; the red rocks and dramatic silhouettes of Sedona; a twisting, turning cliffhanger route through the pines of Oak Creek Canyon; and one more canyon — the Grand. Info: visitarizona.com
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