Celtic Festival, Edinburgh, Scotland, 2003

Red-painted, torch-wielding revelers parade and dance in Edinburgh, Scotland, during the raucous Beltane festival, an ancient Celtic rite that heralds the May 1 start of summer. The popularity of this festival is part of an ongoing push by modern Celts to uncover the lost cultures of their ancestors—music, sacred sites, languages, and art styles that date back more than 2,000 years, when Celtic tribes dominated most of Europe.

(Text adapted from and photo shot on assignment for, but not published in, "Celt Appeal," March 2006, National Geographic magazine)