(WSJ) - The winemakers of Sicily’s Etna region brave hail, rain, snow and an active volcano. But the risks have been outweighed by the rewards; their wines are some of the most interesting being produced in Italy.

GREAT WINEMAKERS thrive on adversity. They embrace marginal climates, temperamental grapes and growing conditions generally ill-suited to the faint of heart. The winemakers of the Etna region of Sicily are a particularly courageous bunch. They risk hail, rain, snow and an active volcano in pursuit of their goal: to produce some of the greatest wines in the world.

“Every year there is something really nutty you don’t understand here,” winemakerMarco de Grazia told me last month as we stood in the courtyard of his Tenuta delle Terre Nere winery on the last day of harvest. For example, a few decades ago, lava buried an entire vineyard. And in 2014, a year that Mr. de Grazia called his “very best,” he lost 20% of his harvest to hail.

But braving the elements—and frequent ash showers—has its rewards. Some of the most interesting and characterful wines in Sicily, if not all of Italy, have been produced here in recent years, thanks to a combination of new talent and great old terroir.

The Etna DOC, the officially recognized growing zone, encompasses vineyards on the northern, eastern and southern slopes of Mount Etna. Its mineral-rich soil, particularly good for growing grapes, is ever-evolving as Etna continues to spew steam, ash and lava. The climate also varies, ranging from alpine temperatures at higher elevations to warmer climes below.

Though these conditions complicate the creation of great wine, critically praised bottlings from wineries such as Mr. de Grazia’s Tenuta delle Terre Nere, Benanti,Passopisciaro and Tenuta di Fessina have made Etna much sought-after by winemakers. The relative bargain price of the region’s vineyard land is another draw. While a hectare (2.47 acres) of great land in Tuscany could cost as much as €1 million ($1.1 million), a planted hectare on Etna’s desirable north side can cost €80,000-€100,000, according to Mr. de Grazia.