Meet the Greeks who call Mount Olympus their spiritual home

Silver-haired and soft-spoken, George Klonis worked as a bus driver into his 60s but found his life's purpose at the foot of Mount Olympus.

With his arms outstretched and his toes touching cold spring water, Klonis offers his devotion to the ancient gods that Greek mythology says made Olympus their home: "Eternal and almighty Zeus, we call on you ... we praise you, and we will always honor your strength."

About 50 men and women, some with wreaths of branches on their heads, some wearing ancient-style tunics, stand in silence behind him with their eyes closed. Several hundred more Greeks, all devotees of ancient Greece's religion and traditions, come to worship, revel in rituals and take part in a range of events every July by the mythic mountain, the country's highest peak at just under 3,000 meters (9,600 feet).

The yearly pilgrimage , started in 1996, draws a...